diff --git a/cpp/test/Ice/optional/AllTests.cpp b/cpp/test/Ice/optional/AllTests.cpp
index 1bc7f86b142..1253299ec1e 100644
--- a/cpp/test/Ice/optional/AllTests.cpp
+++ b/cpp/test/Ice/optional/AllTests.cpp
@@ -204,11 +204,11 @@ class FObjectReader : public Ice::Value
         _f = make_shared<F>();
         in->startValue();
         in->startSlice();
-        // Don't read af on purpose
-        // in.read(1, _f->af);
+        // Don't read fsf on purpose
+        // in.read(1, _f->fsf);
         in->endSlice();
         in->startSlice();
-        in->read(_f->ae);
+        in->read(_f->fse);
         in->endSlice();
         in->endValue();
     }
@@ -644,28 +644,16 @@ allTests(Test::TestHelper* helper, bool)
         factory->setEnabled(false);
     }
 
-    //
-    // Use the 1.0 encoding with operations whose only class parameters are optional.
-    //
-    optional<OneOptionalPtr> oo(make_shared<OneOptional>(53));
-    initial->sendOptionalClass(true, oo);
-    initial->ice_encodingVersion(Ice::Encoding_1_0)->sendOptionalClass(true, oo);
-
-    initial->returnOptionalClass(true, oo);
-    test(oo);
-    initial->ice_encodingVersion(Ice::Encoding_1_0)->returnOptionalClass(true, oo);
-    test(!oo);
-
     GPtr g = make_shared<G>();
-    g->gg1Opt = make_shared<G1>("gg1Opt");
-    g->gg2 = make_shared<G2>(10);
-    g->gg2Opt = make_shared<G2>(20);
-    g->gg1 = make_shared<G1>("gg1");
+    g->gg1Opt = G1{"gg1Opt"};
+    g->gg2 = G2{10};
+    g->gg2Opt = G2{20};
+    g->gg1 = G1{"gg1"};
     GPtr r = initial->opG(g);
-    test("gg1Opt" == r->gg1Opt.value()->a);
-    test(10 == r->gg2->a);
-    test(20 == r->gg2Opt.value()->a);
-    test("gg1" == r->gg1->a);
+    test("gg1Opt" == r->gg1Opt.value().a);
+    test(10 == r->gg2.a);
+    test(20 == r->gg2Opt.value().a);
+    test("gg1" == r->gg1.a);
 
     initial->opVoid();
 
@@ -765,15 +753,15 @@ allTests(Test::TestHelper* helper, bool)
 
     cout << "ok" << endl;
 
-    cout << "testing marshaling of objects with optional objects..." << flush;
+    cout << "testing marshaling of objects with optional members..." << flush;
     {
         FPtr f = make_shared<F>();
 
-        f->af = make_shared<A>();
-        f->ae = *f->af;
+        f->fsf = FixedStruct{56};
+        f->fse = *f->fsf;
 
         FPtr rf = dynamic_pointer_cast<F>(initial->pingPong(f));
-        test(rf->ae == *rf->af);
+        test(rf->fse == *rf->fsf);
 
         factory->setEnabled(true);
         Ice::OutputStream out(communicator);
@@ -789,7 +777,7 @@ allTests(Test::TestHelper* helper, bool)
         factory->setEnabled(false);
 
         rf = dynamic_cast<FObjectReader*>(obj.get())->getF();
-        test(rf->ae && !rf->af);
+        test(rf->fse.m == 56 && !rf->fsf);
     }
     cout << "ok" << endl;
 
@@ -1294,23 +1282,23 @@ allTests(Test::TestHelper* helper, bool)
 
     {
         FPtr f = make_shared<F>();
-        f->af = make_shared<A>();
-        (*f->af)->requiredA = 56;
-        f->ae = *f->af;
+        f->fsf = FixedStruct();
+        (*f->fsf).m = 56;
+        f->fse = *f->fsf;
 
         Ice::OutputStream out(communicator);
         out.startEncapsulation();
         out.write(1, make_optional(f));
-        out.write(2, make_optional(f->ae));
+        out.write(2, make_optional(f->fse));
         out.endEncapsulation();
         out.finished(inEncaps);
 
+        optional<FixedStruct> ofs;
         Ice::InputStream in(communicator, out.getEncoding(), inEncaps);
         in.startEncapsulation();
-        optional<APtr> a;
-        in.read(2, a);
+        in.read(2, ofs);
         in.endEncapsulation();
-        test(a && *a && (*a)->requiredA == 56);
+        test(ofs && (*ofs).m == 56);
     }
     cout << "ok" << endl;
 
diff --git a/cpp/test/Ice/optional/Test.ice b/cpp/test/Ice/optional/Test.ice
index a4b2d581855..4399663da4c 100644
--- a/cpp/test/Ice/optional/Test.ice
+++ b/cpp/test/Ice/optional/Test.ice
@@ -161,20 +161,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -278,10 +278,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/cpp/test/Ice/optional/TestAMD.ice b/cpp/test/Ice/optional/TestAMD.ice
index fe0a1c7e98d..10b7a4e67be 100644
--- a/cpp/test/Ice/optional/TestAMD.ice
+++ b/cpp/test/Ice/optional/TestAMD.ice
@@ -161,20 +161,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -278,10 +278,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/cpp/test/Ice/optional/TestAMDI.cpp b/cpp/test/Ice/optional/TestAMDI.cpp
index 3c4997ff02f..1b0d99515c4 100644
--- a/cpp/test/Ice/optional/TestAMDI.cpp
+++ b/cpp/test/Ice/optional/TestAMDI.cpp
@@ -408,27 +408,6 @@ InitialI::opClassAndUnknownOptionalAsync(
     response();
 }
 
-void
-InitialI::sendOptionalClassAsync(
-    bool,
-    optional<shared_ptr<Test::OneOptional>>,
-    function<void()> response,
-    function<void(exception_ptr)>,
-    const Ice::Current&)
-{
-    response();
-}
-
-void
-InitialI::returnOptionalClassAsync(
-    bool,
-    function<void(const optional<shared_ptr<Test::OneOptional>>&)> response,
-    function<void(exception_ptr)>,
-    const Ice::Current&)
-{
-    response(make_shared<OneOptional>(53));
-}
-
 void
 InitialI::opGAsync(
     shared_ptr<Test::G> g,
diff --git a/cpp/test/Ice/optional/TestAMDI.h b/cpp/test/Ice/optional/TestAMDI.h
index 9b17366f5ad..d4bb286ba8e 100644
--- a/cpp/test/Ice/optional/TestAMDI.h
+++ b/cpp/test/Ice/optional/TestAMDI.h
@@ -261,19 +261,6 @@ class InitialI final : public Test::Initial
         std::function<void(std::exception_ptr)>,
         const Ice::Current&) final;
 
-    void sendOptionalClassAsync(
-        bool,
-        std::optional<std::shared_ptr<Test::OneOptional>>,
-        std::function<void()>,
-        std::function<void(std::exception_ptr)>,
-        const Ice::Current&) final;
-
-    void returnOptionalClassAsync(
-        bool,
-        std::function<void(const std::optional<std::shared_ptr<Test::OneOptional>>&)>,
-        std::function<void(std::exception_ptr)>,
-        const Ice::Current&) final;
-
     void opGAsync(
         std::shared_ptr<Test::G>,
         std::function<void(const std::shared_ptr<Test::G>&)>,
diff --git a/cpp/test/Ice/optional/TestI.cpp b/cpp/test/Ice/optional/TestI.cpp
index 39465b075ab..0eedee5bf3b 100644
--- a/cpp/test/Ice/optional/TestI.cpp
+++ b/cpp/test/Ice/optional/TestI.cpp
@@ -339,17 +339,6 @@ InitialI::opClassAndUnknownOptional(APtr, const Ice::Current&)
 {
 }
 
-void
-InitialI::sendOptionalClass(bool, optional<OneOptionalPtr>, const Ice::Current&)
-{
-}
-
-void
-InitialI::returnOptionalClass(bool, optional<OneOptionalPtr>& o, const Ice::Current&)
-{
-    o = make_shared<OneOptional>(53);
-}
-
 GPtr
 InitialI::opG(GPtr g, const Ice::Current&)
 {
diff --git a/cpp/test/Ice/optional/TestI.h b/cpp/test/Ice/optional/TestI.h
index 2f6f9932b75..5a7f8564bb3 100644
--- a/cpp/test/Ice/optional/TestI.h
+++ b/cpp/test/Ice/optional/TestI.h
@@ -147,10 +147,6 @@ class InitialI : public Test::Initial
 
     virtual void opClassAndUnknownOptional(Test::APtr, const Ice::Current&);
 
-    virtual void sendOptionalClass(bool, std::optional<Test::OneOptionalPtr>, const Ice::Current&);
-
-    virtual void returnOptionalClass(bool, std::optional<Test::OneOptionalPtr>&, const Ice::Current&);
-
     virtual ::Test::GPtr opG(::Test::GPtr g, const Ice::Current&);
 
     virtual void opVoid(const Ice::Current&);
diff --git a/csharp/test/Ice/optional/AllTests.cs b/csharp/test/Ice/optional/AllTests.cs
index 3a678026608..5fe3bf2ded5 100644
--- a/csharp/test/Ice/optional/AllTests.cs
+++ b/csharp/test/Ice/optional/AllTests.cs
@@ -336,19 +336,6 @@ public class AllTests : global::Test.AllTests
                 test(cb.obj != null && cb.obj is TestValueReader);
                 factory.setEnabled(false);
 
-                //
-                // Use the 1.0 encoding with operations whose only class parameters are optional.
-                //
-                var oo = new Ice.Optional<Test.OneOptional>(new Test.OneOptional(53));
-                initial.sendOptionalClass(true, oo);
-                Test.InitialPrx initial2 = (Test.InitialPrx)initial.ice_encodingVersion(Ice.Util.Encoding_1_0);
-                initial2.sendOptionalClass(true, oo);
-
-                initial.returnOptionalClass(true, out oo);
-                test(oo.HasValue);
-                initial2.returnOptionalClass(true, out oo);
-                test(!oo.HasValue);
-
                 Test.G g = new Test.G();
                 g.gg1Opt = new Ice.Optional<Test.G1>(new Test.G1("gg1Opt"));
                 g.gg2 = new Test.G2(10);
@@ -451,16 +438,16 @@ public class AllTests : global::Test.AllTests
                 }
                 output.WriteLine("ok");
 
-                output.Write("testing marshaling of objects with optional objects...");
+                output.Write("testing marshaling of objects with optional members...");
                 output.Flush();
                 {
                     Test.F f = new Test.F();
 
-                    f.af = new Test.A();
-                    f.ae = (Test.A)f.af;
+                    f.fsf = new Test.FixedStruct();
+                    f.fse = (Test.FixedStruct)f.fsf;
 
                     Test.F rf = (Test.F)initial.pingPong(f);
-                    test(rf.ae == rf.af.Value);
+                    test(rf.fse == rf.fsf.Value);
 
                     factory.setEnabled(true);
                     os = new Ice.OutputStream(communicator);
@@ -475,7 +462,7 @@ public class AllTests : global::Test.AllTests
                     @in.endEncapsulation();
                     factory.setEnabled(false);
                     rf = ((FValueReader)rocb.obj).getF();
-                    test(rf.ae != null && !rf.af.HasValue);
+                    test(rf.fse != null && !rf.fsf.HasValue);
                 }
                 output.WriteLine("ok");
 
@@ -1867,27 +1854,26 @@ public class AllTests : global::Test.AllTests
                     @in.endEncapsulation();
 
                     Test.F f = new Test.F();
-                    f.af = new Test.A();
-                    f.af.Value.requiredA = 56;
-                    f.ae = f.af.Value;
+                    f.fsf = new Test.FixedStruct(56);
+                    f.fse = f.fsf.Value;
 
                     os = new OutputStream(communicator);
                     os.startEncapsulation();
                     os.writeOptional(1, OptionalFormat.Class);
                     os.writeValue(f);
-                    os.writeOptional(2, OptionalFormat.Class);
-                    os.writeValue(f.ae);
+                    os.writeOptional(2, OptionalFormat.VSize);
+                    os.writeSize(4);
+                    Test.FixedStruct.ice_write(os, f.fse);
                     os.endEncapsulation();
                     inEncaps = os.finished();
 
                     @in = new InputStream(communicator, inEncaps);
                     @in.startEncapsulation();
-                    test(@in.readOptional(2, OptionalFormat.Class));
-                    ReadValueCallbackI rocb = new ReadValueCallbackI();
-                    @in.readValue(rocb.invoke);
+                    test(@in.readOptional(2, OptionalFormat.VSize));
+                    @in.skipSize();
+                    Test.FixedStruct fs1 = Test.FixedStruct.ice_read(@in);
                     @in.endEncapsulation();
-                    Test.A a = (Test.A)rocb.obj;
-                    test(a != null && a.requiredA == 56);
+                    test(fs1 != null && fs1.m == 56);
                 }
 
                 {
@@ -1978,6 +1964,7 @@ public class AllTests : global::Test.AllTests
                         //
                         // Use the 1.0 encoding with an exception whose only class members are optional.
                         //
+                        Test.InitialPrx initial2 = (Test.InitialPrx)initial.ice_encodingVersion(Ice.Util.Encoding_1_0);
                         Ice.Optional<int> a = new Ice.Optional<int>(30);
                         Ice.Optional<string> b = new Ice.Optional<string>("test");
                         Ice.Optional<Test.OneOptional> o = new Ice.Optional<Test.OneOptional>(new Test.OneOptional(53));
@@ -2333,15 +2320,13 @@ public override void read(Ice.InputStream @in)
                     _f = new Test.F();
                     @in.startValue();
                     @in.startSlice();
-                    // Don't read af on purpose
-                    //in.read(1, _f.af);
+                    // Don't read fsf on purpose
+                    //@in.read(1, _f.fsf);
                     @in.endSlice();
                     @in.startSlice();
-                    ReadValueCallbackI rocb = new ReadValueCallbackI();
-                    @in.readValue(rocb.invoke);
+                    _f.fse = Test.FixedStruct.ice_read(@in);
                     @in.endSlice();
                     @in.endValue();
-                    _f.ae = (Test.A)rocb.obj;
                 }
 
                 public Test.F getF()
diff --git a/csharp/test/Ice/optional/Test.ice b/csharp/test/Ice/optional/Test.ice
index db35ee53afb..63ee679428d 100644
--- a/csharp/test/Ice/optional/Test.ice
+++ b/csharp/test/Ice/optional/Test.ice
@@ -156,20 +156,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -260,10 +260,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/csharp/test/Ice/optional/TestAMD.ice b/csharp/test/Ice/optional/TestAMD.ice
index e9959750300..9384f1852f3 100644
--- a/csharp/test/Ice/optional/TestAMD.ice
+++ b/csharp/test/Ice/optional/TestAMD.ice
@@ -156,20 +156,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -261,10 +261,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/csharp/test/Ice/optional/TestAMDI.cs b/csharp/test/Ice/optional/TestAMDI.cs
index eec672f9382..88d1ebdec26 100644
--- a/csharp/test/Ice/optional/TestAMDI.cs
+++ b/csharp/test/Ice/optional/TestAMDI.cs
@@ -245,18 +245,6 @@ public override Task
                     return null;
                 }
 
-                public override Task
-                sendOptionalClassAsync(bool req, Ice.Optional<Test.OneOptional> o, Ice.Current current)
-                {
-                    return null;
-                }
-
-                public override Task<Ice.Optional<Test.OneOptional>>
-                returnOptionalClassAsync(bool req, Ice.Current current)
-                {
-                    return Task.FromResult(new Ice.Optional<Test.OneOptional>(new Test.OneOptional(53)));
-                }
-
                 public override Task<Test.G>
                 opGAsync(Test.G g, Ice.Current current)
                 {
diff --git a/csharp/test/Ice/optional/TestI.cs b/csharp/test/Ice/optional/TestI.cs
index 0a0c4a639f3..7a51af67b2b 100644
--- a/csharp/test/Ice/optional/TestI.cs
+++ b/csharp/test/Ice/optional/TestI.cs
@@ -305,19 +305,6 @@ public override void opClassAndUnknownOptional(Test.A p, Ice.Current current)
             {
             }
 
-            public override void sendOptionalClass(bool req,
-                                                   Ice.Optional<Test.OneOptional> o,
-                                                   Ice.Current current)
-            {
-            }
-
-            public override void returnOptionalClass(bool req,
-                                                     out Ice.Optional<Test.OneOptional> o,
-                                                     Ice.Current current)
-            {
-                o = new Test.OneOptional(53);
-            }
-
             public override Test.G opG(Test.G g, Ice.Current current)
             {
                 return g;
diff --git a/java/test/src/main/java/test/Ice/optional/AMDInitialI.java b/java/test/src/main/java/test/Ice/optional/AMDInitialI.java
index d2ef55801da..0188c3731bf 100644
--- a/java/test/src/main/java/test/Ice/optional/AMDInitialI.java
+++ b/java/test/src/main/java/test/Ice/optional/AMDInitialI.java
@@ -465,18 +465,6 @@ public CompletionStage<Void> opClassAndUnknownOptionalAsync(A p, Current current
     return CompletableFuture.completedFuture(null);
   }
 
-  @Override
-  public CompletionStage<Void> sendOptionalClassAsync(
-      boolean req, Optional<OneOptional> o, Current current) {
-    return CompletableFuture.completedFuture(null);
-  }
-
-  @Override
-  public CompletionStage<Optional<OneOptional>> returnOptionalClassAsync(
-      boolean req, Current current) {
-    return CompletableFuture.completedFuture(Optional.of(new OneOptional(53)));
-  }
-
   @Override
   public CompletionStage<G> opGAsync(G g, Current current) {
     return CompletableFuture.completedFuture(g);
diff --git a/java/test/src/main/java/test/Ice/optional/AllTests.java b/java/test/src/main/java/test/Ice/optional/AllTests.java
index 6e2b9ebe773..44a242b33b8 100644
--- a/java/test/src/main/java/test/Ice/optional/AllTests.java
+++ b/java/test/src/main/java/test/Ice/optional/AllTests.java
@@ -376,19 +376,6 @@ public static InitialPrx allTests(test.TestHelper helper, boolean collocated) {
     test(cb.value != null);
     factory.setEnabled(false);
 
-    //
-    // Use the 1.0 encoding with operations whose only class parameters are optional.
-    //
-    Optional<OneOptional> oo = Optional.of(new OneOptional(53));
-    initial.sendOptionalClass(true, oo);
-    InitialPrx initial2 = initial.ice_encodingVersion(com.zeroc.Ice.Util.Encoding_1_0);
-    initial2.sendOptionalClass(true, oo);
-
-    oo = initial.returnOptionalClass(true);
-    test(oo.isPresent());
-    oo = initial2.returnOptionalClass(true);
-    test(!oo.isPresent());
-
     G g = new G();
     g.setGg1Opt(new G1("gg1Opt"));
     g.gg2 = new G2(10);
@@ -493,16 +480,16 @@ public static InitialPrx allTests(test.TestHelper helper, boolean collocated) {
     }
     out.println("ok");
 
-    out.print("testing marshaling of objects with optional objects...");
+    out.print("testing marshaling of objects with optional members...");
     out.flush();
     {
       F f = new F();
 
-      f.setAf(new A());
-      f.ae = f.getAf();
+      f.setFsf(new FixedStruct());
+      f.fse = f.getFsf();
 
       F rf = (F) initial.pingPong(f);
-      test(rf.ae == rf.getAf());
+      test(rf.fse.equals(rf.getFsf()));
 
       factory.setEnabled(true);
       os = new OutputStream(communicator);
@@ -516,7 +503,7 @@ public static InitialPrx allTests(test.TestHelper helper, boolean collocated) {
       in.readValue(v -> w.value = v.getF(), FObjectReader.class);
       in.endEncapsulation();
       factory.setEnabled(false);
-      test(w.value.ae != null && !w.value.hasAf());
+      test(w.value.fse != null && !w.value.hasFsf());
     }
     out.println("ok");
 
@@ -1963,25 +1950,27 @@ public static InitialPrx allTests(test.TestHelper helper, boolean collocated) {
 
     {
       F f = new F();
-      f.setAf(new A());
-      f.getAf().requiredA = 56;
-      f.ae = f.getAf();
+      f.setFsf(new FixedStruct());
+      f.getFsf().m = 56;
+      f.fse = f.getFsf();
 
       os = new OutputStream(communicator);
       os.startEncapsulation();
       os.writeOptional(1, OptionalFormat.Class);
       os.writeValue(f);
-      os.writeOptional(2, OptionalFormat.Class);
-      os.writeValue(f.ae);
+      os.writeOptional(2, OptionalFormat.VSize);
+      os.writeSize(4);
+      FixedStruct.ice_write(os, f.fse);
       os.endEncapsulation();
       inEncaps = os.finished();
 
       in = new InputStream(communicator, inEncaps);
       in.startEncapsulation();
-      final Wrapper<java.util.Optional<A>> w = new Wrapper<>();
-      in.readValue(2, v -> w.value = v, A.class);
+      test(in.readOptional(2, OptionalFormat.VSize));
+      in.skipSize();
+      FixedStruct fs1 = FixedStruct.ice_read(in);
       in.endEncapsulation();
-      test(w.value.get() != null && w.value.get().requiredA == 56);
+      test(fs1 != null && fs1.m == 56);
     }
     out.println("ok");
 
@@ -2014,6 +2003,7 @@ public static InitialPrx allTests(test.TestHelper helper, boolean collocated) {
         //
         // Use the 1.0 encoding with an exception whose only class members are optional.
         //
+        InitialPrx initial2 = initial.ice_encodingVersion(com.zeroc.Ice.Util.Encoding_1_0);
         OptionalInt a = OptionalInt.of(30);
         Optional<String> b = Optional.of("test");
         Optional<OneOptional> o = Optional.of(new OneOptional(53));
@@ -2255,11 +2245,11 @@ public void read(InputStream in) {
       _f = new F();
       in.startValue();
       in.startSlice();
-      // Don't read af on purpose
-      // in.read(1, _f.af);
+      // Don't read fsf on purpose
+      // in.read(1, _f.fsf);
       in.endSlice();
       in.startSlice();
-      in.readValue(v -> _f.ae = v, A.class);
+      _f.fse = FixedStruct.ice_read(in);
       in.endSlice();
       in.endValue();
     }
diff --git a/java/test/src/main/java/test/Ice/optional/InitialI.java b/java/test/src/main/java/test/Ice/optional/InitialI.java
index 8c332002674..2a0d90e7975 100644
--- a/java/test/src/main/java/test/Ice/optional/InitialI.java
+++ b/java/test/src/main/java/test/Ice/optional/InitialI.java
@@ -435,14 +435,6 @@ public Initial.OpIntOneOptionalDictReqResult opIntOneOptionalDictReq(
   @Override
   public void opClassAndUnknownOptional(A p, Current current) {}
 
-  @Override
-  public void sendOptionalClass(boolean req, Optional<OneOptional> o, Current current) {}
-
-  @Override
-  public Optional<OneOptional> returnOptionalClass(boolean req, Current current) {
-    return Optional.of(new OneOptional(53));
-  }
-
   @Override
   public G opG(G g, Current current) {
     return g;
diff --git a/java/test/src/main/java/test/Ice/optional/Test.ice b/java/test/src/main/java/test/Ice/optional/Test.ice
index 465a50b01ba..95ffc42a33a 100644
--- a/java/test/src/main/java/test/Ice/optional/Test.ice
+++ b/java/test/src/main/java/test/Ice/optional/Test.ice
@@ -158,20 +158,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -307,11 +307,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    ["java:optional"]
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/java/test/src/main/java/test/Ice/optional/TestAMD.ice b/java/test/src/main/java/test/Ice/optional/TestAMD.ice
index e94daa9f0c2..f7e78cf862d 100644
--- a/java/test/src/main/java/test/Ice/optional/TestAMD.ice
+++ b/java/test/src/main/java/test/Ice/optional/TestAMD.ice
@@ -158,20 +158,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -309,11 +309,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    ["java:optional"]
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/js/test/Ice/optional/AMDInitialI.js b/js/test/Ice/optional/AMDInitialI.js
index f4e71b7ad40..25be7a9fe93 100644
--- a/js/test/Ice/optional/AMDInitialI.js
+++ b/js/test/Ice/optional/AMDInitialI.js
@@ -253,15 +253,6 @@
         {
         }
 
-        sendOptionalClass(req, current)
-        {
-        }
-
-        returnOptionalClass(req, current)
-        {
-            return new Test.OneOptional(53);
-        }
-
         opG(g, current)
         {
             return g;
diff --git a/js/test/Ice/optional/Client.js b/js/test/Ice/optional/Client.js
index f85929cbd0f..70721f50e45 100644
--- a/js/test/Ice/optional/Client.js
+++ b/js/test/Ice/optional/Client.js
@@ -253,19 +253,6 @@
 
             test(mo9.bos === undefined);
 
-            //
-            // Use the 1.0 encoding with operations whose only class parameters are optional.
-            //
-            const initial2 = initial.ice_encodingVersion(Ice.Encoding_1_0);
-            const oo = new Test.OneOptional(53);
-
-            await initial.sendOptionalClass(true, oo);
-            await initial2.sendOptionalClass(true, oo);
-            oo1 = await initial.returnOptionalClass(true);
-            test(oo1 !== undefined && oo1.a == 53);
-            oo1 = await initial2.returnOptionalClass(true);
-            test(oo1 === undefined);
-
             let g = new Test.G();
             g.gg1Opt = new Test.G1("gg1Opt");
             g.gg2 = new Test.G2(new Ice.Long(0, 10));
@@ -329,12 +316,12 @@
             test(b.md == 13);
             out.writeLine("ok");
 
-            out.write("testing marshaling of objects with optional objects... ");
+            out.write("testing marshaling of objects with optional members... ");
             let f = new Test.F();
-            f.af = new Test.A();
-            f.ae = f.af;
+            f.fsf = new Test.FixedStruct();
+            f.fse = f.fsf;
             f = await initial.pingPong(f);
-            test(f.ae === f.af);
+            test(f.fse.equals(f.fsf));
             out.writeLine("ok");
 
             out.write("testing optional with default values... ");
diff --git a/js/test/Ice/optional/InitialI.js b/js/test/Ice/optional/InitialI.js
index 1a5c83ba4cc..ac45092b47d 100644
--- a/js/test/Ice/optional/InitialI.js
+++ b/js/test/Ice/optional/InitialI.js
@@ -253,10 +253,6 @@
         {
         }
 
-        sendOptionalClass(req, current)
-        {
-        }
-
         opG(g, current)
         {
             return g;
@@ -306,11 +302,6 @@
             return [p1, p1];
         }
 
-        returnOptionalClass(req, current)
-        {
-            return new Test.OneOptional(53);
-        }
-
         supportsRequiredParams(current)
         {
             return false;
diff --git a/js/test/Ice/optional/Test.ice b/js/test/Ice/optional/Test.ice
index 340ef8ff2f9..15c44c0c8e0 100644
--- a/js/test/Ice/optional/Test.ice
+++ b/js/test/Ice/optional/Test.ice
@@ -157,20 +157,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -263,10 +263,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/js/test/typescript/Ice/optional/AMDInitialI.ts b/js/test/typescript/Ice/optional/AMDInitialI.ts
index 7794c998b4b..84fae160e28 100644
--- a/js/test/typescript/Ice/optional/AMDInitialI.ts
+++ b/js/test/typescript/Ice/optional/AMDInitialI.ts
@@ -252,15 +252,6 @@ export class AMDInitialI extends Test.Initial
     {
     }
 
-    sendOptionalClass(req:boolean, one:Test.OneOptional, current:Ice.Current):void
-    {
-    }
-
-    returnOptionalClass(req:boolean, current:Ice.Current):Test.OneOptional
-    {
-        return new Test.OneOptional(53);
-    }
-
     opG(g:Test.G, current:Ice.Current):Test.G
     {
         return g;
diff --git a/js/test/typescript/Ice/optional/Client.ts b/js/test/typescript/Ice/optional/Client.ts
index 67ac4721882..2d99c7bfb2c 100644
--- a/js/test/typescript/Ice/optional/Client.ts
+++ b/js/test/typescript/Ice/optional/Client.ts
@@ -250,19 +250,6 @@ export class Client extends TestHelper
 
         test(mo9.bos === undefined);
 
-        //
-        // Use the 1.0 encoding with operations whose only class parameters are optional.
-        //
-        const initial2 = initial.ice_encodingVersion(Ice.Encoding_1_0);
-        const oo = new Test.OneOptional(53);
-
-        await initial.sendOptionalClass(true, oo);
-        await initial2.sendOptionalClass(true, oo);
-        oo1 = await initial.returnOptionalClass(true);
-        test(oo1 !== undefined && oo1.a == 53);
-        oo1 = await initial2.returnOptionalClass(true);
-        test(oo1 === undefined);
-
         let g = new Test.G();
         g.gg1Opt = new Test.G1("gg1Opt");
         g.gg2 = new Test.G2(new Ice.Long(0, 10));
@@ -326,12 +313,12 @@ export class Client extends TestHelper
         test(b.md == 13);
         out.writeLine("ok");
 
-        out.write("testing marshaling of objects with optional objects... ");
+        out.write("testing marshaling of objects with optional members... ");
         let f = new Test.F();
-        f.af = new Test.A();
-        f.ae = f.af;
+        f.fsf = new Test.FixedStruct();
+        f.fse = f.fsf;
         f = await initial.pingPong(f) as Test.F;
-        test(f.ae === f.af);
+        test(f.fse.equals(f.fsf));
         out.writeLine("ok");
 
         out.write("testing optional with default values... ");
diff --git a/js/test/typescript/Ice/optional/InitialI.ts b/js/test/typescript/Ice/optional/InitialI.ts
index 59a0cdd08fa..68aad568d42 100644
--- a/js/test/typescript/Ice/optional/InitialI.ts
+++ b/js/test/typescript/Ice/optional/InitialI.ts
@@ -252,15 +252,6 @@ export class InitialI extends Test.Initial
     {
     }
 
-    sendOptionalClass(req:boolean, one:Test.OneOptional, current:Ice.Current):void
-    {
-    }
-
-    returnOptionalClass(req:boolean, current:Ice.Current):Test.OneOptional
-    {
-        return new Test.OneOptional(53);
-    }
-
     opG(g:Test.G, current:Ice.Current):Test.G
     {
         return g;
diff --git a/js/test/typescript/Ice/optional/Test.ice b/js/test/typescript/Ice/optional/Test.ice
index fbcc13a5104..91e359cc7f4 100644
--- a/js/test/typescript/Ice/optional/Test.ice
+++ b/js/test/typescript/Ice/optional/Test.ice
@@ -159,20 +159,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -265,10 +265,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/matlab/test/Ice/optional/AllTests.m b/matlab/test/Ice/optional/AllTests.m
index a90ed02065e..6047dfc8ea4 100644
--- a/matlab/test/Ice/optional/AllTests.m
+++ b/matlab/test/Ice/optional/AllTests.m
@@ -298,17 +298,6 @@
 
             assert(mo9.bos == Ice.Unset);
 
-            %
-            % Use the 1.0 encoding with operations whose only class parameters are optional.
-            %
-            initial.sendOptionalClass(true, OneOptional(53));
-            initial.ice_encodingVersion(Ice.EncodingVersion(1, 0)).sendOptionalClass(true, OneOptional(53));
-
-            r = initial.returnOptionalClass(true);
-            assert(r ~= Ice.Unset)
-            r = initial.ice_encodingVersion(Ice.EncodingVersion(1, 0)).returnOptionalClass(true);
-            assert(r == Ice.Unset);
-
             g = G();
             g.gg1Opt = G1('gg1Opt');
             g.gg2 = G2(10);
@@ -371,15 +360,15 @@
 
             fprintf('ok\n');
 
-            fprintf('testing marshaling of objects with optional objects... ');
+            fprintf('testing marshaling of objects with optional members... ');
 
             f = F();
 
-            f.af = A();
-            f.ae = f.af;
+            f.fsf = FixedStruct();
+            f.fse = f.fsf;
 
             rf = initial.pingPong(f);
-            assert(rf.ae == rf.af);
+            assert(rf.fse == rf.fsf);
 
             fprintf('ok\n');
 
diff --git a/matlab/test/Ice/optional/Test.ice b/matlab/test/Ice/optional/Test.ice
index 5b6ce93daca..f395b6c0289 100644
--- a/matlab/test/Ice/optional/Test.ice
+++ b/matlab/test/Ice/optional/Test.ice
@@ -158,20 +158,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -271,10 +271,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/php/test/Ice/optional/Client.php b/php/test/Ice/optional/Client.php
index c28e136ae66..58c9cae39c1 100644
--- a/php/test/Ice/optional/Client.php
+++ b/php/test/Ice/optional/Client.php
@@ -293,18 +293,6 @@ function allTests($helper)
 
     test($mo9->bos == Ice\None);
 
-    //
-    // Use the 1.0 encoding with operations whose only class parameters are optional.
-    //
-    $oo = new Test\OneOptional(53);
-    $initial->sendOptionalClass(true, $oo);
-    $initial->ice_encodingVersion($Ice_Encoding_1_0)->sendOptionalClass(true, $oo);
-
-    $initial->returnOptionalClass(true, $oo);
-    test($oo != Ice\None);
-    $initial->ice_encodingVersion($Ice_Encoding_1_0)->returnOptionalClass(true, $oo);
-    test($oo == Ice\None);
-
     $g = new Test\G;
     $g->gg1Opt = new Test\G1("gg1Opt");
     $g->gg2 = new Test\G2(10);
@@ -376,16 +364,16 @@ function allTests($helper)
 
     echo "ok\n";
 
-    echo "testing marshaling of objects with optional objects...";
+    echo "testing marshaling of objects with optional members...";
     flush();
 
     $f = new Test\F;
 
-    $f->af = new Test\A;
-    $f->ae = $f->af;
+    $f->fsf = new Test\FixedStruct;
+    $f->fse = $f->fsf;
 
     $rf = $initial->pingPong($f);
-    test($rf->ae == $rf->af);
+    test($rf->fse == $rf->fsf);
 
     echo "ok\n";
 
diff --git a/php/test/Ice/optional/Test.ice b/php/test/Ice/optional/Test.ice
index f7243c9afd3..d571918dc9f 100644
--- a/php/test/Ice/optional/Test.ice
+++ b/php/test/Ice/optional/Test.ice
@@ -157,20 +157,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -263,10 +263,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     ["marshaled-result"] optional(1) SmallStruct opMStruct1();
diff --git a/python/test/Ice/optional/AllTests.py b/python/test/Ice/optional/AllTests.py
index 84ca51aeb6c..407aaf3b73a 100644
--- a/python/test/Ice/optional/AllTests.py
+++ b/python/test/Ice/optional/AllTests.py
@@ -328,19 +328,6 @@ def allTests(helper, communicator):
 
     test(mo9.bos is Ice.Unset)
 
-    #
-    # Use the 1.0 encoding with operations whose only class parameters are optional.
-    #
-    initial.sendOptionalClass(True, Test.OneOptional(53))
-    initial.ice_encodingVersion(Ice.Encoding_1_0).sendOptionalClass(
-        True, Test.OneOptional(53)
-    )
-
-    r = initial.returnOptionalClass(True)
-    test(r != Ice.Unset)
-    r = initial.ice_encodingVersion(Ice.Encoding_1_0).returnOptionalClass(True)
-    test(r is Ice.Unset)
-
     g = Test.G()
     g.gg1Opt = Test.G1("gg1Opt")
     g.gg2 = Test.G2(10)
@@ -409,16 +396,16 @@ def allTests(helper, communicator):
 
     print("ok")
 
-    sys.stdout.write("testing marshaling of objects with optional objects...")
+    sys.stdout.write("testing marshaling of objects with optional members...")
     sys.stdout.flush()
 
     f = Test.F()
 
-    f.af = Test.A()
-    f.ae = f.af
+    f.fsf = Test.FixedStruct()
+    f.fse = f.fsf
 
     rf = initial.pingPong(f)
-    test(rf.ae == rf.af)
+    test(rf.fse == rf.fsf)
 
     print("ok")
 
diff --git a/python/test/Ice/optional/Server.py b/python/test/Ice/optional/Server.py
index aea542c92e1..31a16fd4199 100755
--- a/python/test/Ice/optional/Server.py
+++ b/python/test/Ice/optional/Server.py
@@ -130,12 +130,6 @@ def opIntOneOptionalDict(self, p1, current=None):
     def opClassAndUnknownOptional(self, p, current=None):
         pass
 
-    def sendOptionalClass(self, req, o, current=None):
-        pass
-
-    def returnOptionalClass(self, req, current=None):
-        return Test.OneOptional(53)
-
     def opG(self, g, current=None):
         return g
 
diff --git a/python/test/Ice/optional/ServerAMD.py b/python/test/Ice/optional/ServerAMD.py
index 97e66ffb706..c6d02101d05 100755
--- a/python/test/Ice/optional/ServerAMD.py
+++ b/python/test/Ice/optional/ServerAMD.py
@@ -136,12 +136,6 @@ def opIntOneOptionalDict(self, p1, current=None):
     def opClassAndUnknownOptional(self, p, current=None):
         return Ice.Future.completed(None)
 
-    def sendOptionalClass(self, req, o, current=None):
-        return Ice.Future.completed(None)
-
-    def returnOptionalClass(self, req, current=None):
-        return Ice.Future.completed(Test.OneOptional(53))
-
     def opG(self, g, current=None):
         return Ice.Future.completed(g)
 
diff --git a/python/test/Ice/optional/Test.ice b/python/test/Ice/optional/Test.ice
index 85fd3f5bbb7..8781edbb972 100644
--- a/python/test/Ice/optional/Test.ice
+++ b/python/test/Ice/optional/Test.ice
@@ -157,20 +157,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -267,10 +267,6 @@ interface Initial
     void opOptionalAfterRequired(int p1, optional(1) int p2, optional(2) int p3, out int p4, out optional(3) int p5,
                                  out optional(4) int p6);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/ruby/test/Ice/optional/AllTests.rb b/ruby/test/Ice/optional/AllTests.rb
index ba7a19df583..1fba65d14b1 100644
--- a/ruby/test/Ice/optional/AllTests.rb
+++ b/ruby/test/Ice/optional/AllTests.rb
@@ -291,17 +291,6 @@ def allTests(helper, communicator)
 
     test(mo9.bos == Ice::Unset)
 
-    #
-    # Use the 1.0 encoding with operations whose only class parameters are optional.
-    #
-    initial.sendOptionalClass(true, Test::OneOptional.new(53))
-    initial.ice_encodingVersion(Ice::Encoding_1_0).sendOptionalClass(true, Test::OneOptional.new(53))
-
-    r = initial.returnOptionalClass(true)
-    test(r != Ice::Unset)
-    r = initial.ice_encodingVersion(Ice::Encoding_1_0).returnOptionalClass(true)
-    test(r == Ice::Unset)
-
     g = Test::G.new
     g.gg1Opt = Test::G1.new("gg1Opt")
     g.gg2 = Test::G2.new(10)
@@ -372,16 +361,16 @@ def allTests(helper, communicator)
 
     puts "ok"
 
-    print "testing marshaling of objects with optional objects..."
+    print "testing marshaling of objects with optional members..."
     STDOUT.flush
 
     f = Test::F.new
 
-    f.af = Test::A.new
-    f.ae = f.af
+    f.fsf = Test::FixedStruct.new
+    f.fse = f.fsf
 
     rf = initial.pingPong(f)
-    test(rf.ae == rf.af)
+    test(rf.fse == rf.fsf)
 
     puts "ok"
 
diff --git a/ruby/test/Ice/optional/Test.ice b/ruby/test/Ice/optional/Test.ice
index a726c0e28d9..ba8f107e5cc 100644
--- a/ruby/test/Ice/optional/Test.ice
+++ b/ruby/test/Ice/optional/Test.ice
@@ -157,20 +157,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -263,10 +263,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/swift/test/Ice/optional/AllTests.swift b/swift/test/Ice/optional/AllTests.swift
index ccb661d0ef7..14badaad761 100644
--- a/swift/test/Ice/optional/AllTests.swift
+++ b/swift/test/Ice/optional/AllTests.swift
@@ -129,11 +129,11 @@ class FValueReader: Ice.Value {
     _f = F()
     istr.startValue()
     _ = try istr.startSlice()
-    // Don't read af on purpose
-    // in.read(1, _f.af);
+    // Don't read fsf on purpose
+    // in.read(1, _f.fsf);
     try istr.endSlice()
     _ = try istr.startSlice()
-    try istr.read(A.self) { self._f.ae = $0 }
+    self._f.fse = try istr.read()
     try istr.endSlice()
     _ = try istr.endValue()
   }
@@ -546,20 +546,7 @@ func allTests(_ helper: TestHelper) throws -> InitialPrx {
   }
   factory.setEnabled(enabled: false)
 
-  //
-  // Use the 1.0 encoding with operations whose only class parameters are optional.
-  //
   do {
-    var oo: OneOptional? = OneOptional(a: 53)
-    try initial.sendOptionalClass(req: true, o: oo)
-    let initial2 = initial.ice_encodingVersion(Ice.Encoding_1_0)
-    try initial2.sendOptionalClass(req: true, o: oo)
-
-    oo = try initial.returnOptionalClass(true)
-    try test(oo != nil && oo!.a == 53)
-    oo = try initial2.returnOptionalClass(true)
-    try test(oo == nil)
-
     var g: G! = G()
     g.gg1Opt = G1(a: "gg1Opt")
     g.gg2 = G2(a: 10)
@@ -567,9 +554,9 @@ func allTests(_ helper: TestHelper) throws -> InitialPrx {
     g.gg1 = G1(a: "gg1")
     g = try initial.opG(g)
     try test(g.gg1Opt!.a == "gg1Opt")
-    try test(g.gg2!.a == 10)
+    try test(g.gg2.a == 10)
     try test(g.gg2Opt!.a == 20)
-    try test(g.gg1!.a == "gg1")
+    try test(g.gg1.a == "gg1")
 
     try initial.opVoid()
 
@@ -660,15 +647,15 @@ func allTests(_ helper: TestHelper) throws -> InitialPrx {
   }
   output.writeLine("ok")
 
-  output.write("testing marshaling of objects with optional objects...")
+  output.write("testing marshaling of objects with optional members...")
   do {
     let f = F()
 
-    f.af = A()
-    f.ae = f.af
+    f.fsf = FixedStruct()
+    f.fse = f.fsf!
 
     var rf = try initial.pingPong(f) as! F
-    try test(rf.ae === rf.af)
+    try test(rf.fse == rf.fsf)
 
     factory.setEnabled(enabled: true)
     let ostr = Ice.OutputStream(communicator: communicator)
@@ -683,7 +670,7 @@ func allTests(_ helper: TestHelper) throws -> InitialPrx {
     try istr.endEncapsulation()
     factory.setEnabled(enabled: false)
     rf = (v as! FValueReader).getF()!
-    try test(rf.ae != nil && rf.af == nil)
+    try test(rf.fse.m == 0 && rf.fsf == nil)
   }
   output.writeLine("ok")
 
@@ -3080,23 +3067,22 @@ func allTests(_ helper: TestHelper) throws -> InitialPrx {
     try istr.endEncapsulation()
 
     let f = F()
-    f.af = A()
-    f.af!.requiredA = 56
-    f.ae = f.af
+    f.fsf = FixedStruct()
+    f.fsf!.m = 56
+    f.fse = f.fsf!
 
     ostr = Ice.OutputStream(communicator: communicator)
     ostr.startEncapsulation()
     ostr.write(tag: 1, value: f)
-    ostr.write(tag: 2, value: f.ae)
+    ostr.write(tag: 2, value: f.fse)
     ostr.endEncapsulation()
     inEncaps = ostr.finished()
 
     istr = Ice.InputStream(communicator: communicator, bytes: inEncaps)
     _ = try istr.startEncapsulation()
-    var a: Value?
-    try istr.read(tag: 2) { a = $0 }
+    let fs1: FixedStruct? = try istr.read(tag: 2)
     try istr.endEncapsulation()
-    try test(a != nil && (a as! A).requiredA == 56)
+    try test(fs1 != nil && fs1!.m == 56)
   }
 
   do {
diff --git a/swift/test/Ice/optional/Test.ice b/swift/test/Ice/optional/Test.ice
index 10a4c8fd605..1348e421a83 100644
--- a/swift/test/Ice/optional/Test.ice
+++ b/swift/test/Ice/optional/Test.ice
@@ -161,20 +161,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -270,10 +270,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/swift/test/Ice/optional/TestAMD.ice b/swift/test/Ice/optional/TestAMD.ice
index ec40d60ad5a..57d31dee89a 100644
--- a/swift/test/Ice/optional/TestAMD.ice
+++ b/swift/test/Ice/optional/TestAMD.ice
@@ -159,20 +159,20 @@ class OptionalWithCustom
 
 class E
 {
-    A ae;
+    FixedStruct fse;
 }
 
 class F extends E
 {
-    optional(1) A af;
+    optional(1) FixedStruct fsf;
 }
 
-class G1
+struct G1
 {
     string a;
 }
 
-class G2
+struct G2
 {
     long a;
 }
@@ -266,10 +266,6 @@ interface Initial
 
     void opClassAndUnknownOptional(A p);
 
-    void sendOptionalClass(bool req, optional(1) OneOptional o);
-
-    void returnOptionalClass(bool req, out optional(1) OneOptional o);
-
     G opG(G g);
 
     void opVoid();
diff --git a/swift/test/Ice/optional/TestAMDI.swift b/swift/test/Ice/optional/TestAMDI.swift
index e3cf8c923ca..7e31b87ae72 100644
--- a/swift/test/Ice/optional/TestAMDI.swift
+++ b/swift/test/Ice/optional/TestAMDI.swift
@@ -250,14 +250,6 @@ class InitialI: Initial {
     return Promise.value(())
   }
 
-  func sendOptionalClassAsync(req _: Bool, o _: OneOptional?, current _: Current) -> Promise<Void> {
-    return Promise.value(())
-  }
-
-  func returnOptionalClassAsync(req _: Bool, current _: Current) -> Promise<OneOptional?> {
-    return Promise.value(OneOptional(a: 53))
-  }
-
   func opGAsync(g: G?, current _: Current) -> Promise<G?> {
     return Promise.value(g)
   }
diff --git a/swift/test/Ice/optional/TestI.swift b/swift/test/Ice/optional/TestI.swift
index f9692386f05..d6370629154 100644
--- a/swift/test/Ice/optional/TestI.swift
+++ b/swift/test/Ice/optional/TestI.swift
@@ -250,12 +250,6 @@ class InitialI: Initial {
 
   func opClassAndUnknownOptional(p _: A?, current _: Ice.Current) throws {}
 
-  func sendOptionalClass(req _: Bool, o _: OneOptional?, current _: Ice.Current) throws {}
-
-  func returnOptionalClass(req _: Bool, current _: Ice.Current) throws -> OneOptional? {
-    return OneOptional(a: 53)
-  }
-
   func opG(g: G?, current _: Ice.Current) throws -> G? {
     return g
   }