diff --git a/app/code/core/Mage/Catalog/Model/Product.php b/app/code/core/Mage/Catalog/Model/Product.php
index 956372bdf0f..4cf07c42b8b 100644
--- a/app/code/core/Mage/Catalog/Model/Product.php
+++ b/app/code/core/Mage/Catalog/Model/Product.php
@@ -126,7 +126,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('catalog')->getOldFieldMap();
         return $this;
     }
 
diff --git a/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php b/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php
index 83a5983278d..f66d2b03ade 100644
--- a/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php
+++ b/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php
@@ -152,6 +152,7 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
+        // pre 1.6 fields names, old => new
         $this->_oldFieldsMap = array(
             'stock_status_changed_automatically' => 'stock_status_changed_auto',
             'use_config_enable_qty_increments'   => 'use_config_enable_qty_inc'
diff --git a/app/code/core/Mage/Sales/Model/Order.php b/app/code/core/Mage/Sales/Model/Order.php
index 0d2b9b55002..0f560fe8f02 100644
--- a/app/code/core/Mage/Sales/Model/Order.php
+++ b/app/code/core/Mage/Sales/Model/Order.php
@@ -431,7 +431,12 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'payment_authorization_expiration' => 'payment_auth_expiration',
+            'forced_do_shipment_with_invoice' => 'forced_shipment_with_invoice',
+            'base_shipping_hidden_tax_amount' => 'base_shipping_hidden_tax_amnt',
+        ];
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Address.php b/app/code/core/Mage/Sales/Model/Order/Address.php
index 44c8bb68337..fbbfdb6e79d 100644
--- a/app/code/core/Mage/Sales/Model/Order/Address.php
+++ b/app/code/core/Mage/Sales/Model/Order/Address.php
@@ -93,7 +93,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_address');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Creditmemo.php b/app/code/core/Mage/Sales/Model/Order/Creditmemo.php
index 8e30f7c5f10..809ecb1be53 100644
--- a/app/code/core/Mage/Sales/Model/Order/Creditmemo.php
+++ b/app/code/core/Mage/Sales/Model/Order/Creditmemo.php
@@ -185,7 +185,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_creditmemo');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php b/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php
index 4f57f930142..94454ad771e 100644
--- a/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php
+++ b/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php
@@ -132,7 +132,10 @@ public function setCreditmemo(Mage_Sales_Model_Order_Creditmemo $creditmemo)
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('creditmemo_item');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'base_weee_tax_applied_row_amount' => 'base_weee_tax_applied_row_amnt',
+        ];
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Invoice.php b/app/code/core/Mage/Sales/Model/Order/Invoice.php
index aa1769c7b28..1d2ae85d537 100644
--- a/app/code/core/Mage/Sales/Model/Order/Invoice.php
+++ b/app/code/core/Mage/Sales/Model/Order/Invoice.php
@@ -204,7 +204,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_invoice');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php b/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php
index 87d8ba07343..d94d9e7c995 100644
--- a/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php
+++ b/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php
@@ -122,7 +122,10 @@ function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('invoice_item');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'base_weee_tax_applied_row_amount' => 'base_weee_tax_applied_row_amnt',
+        ];
         return $this;
     }
     /**
diff --git a/app/code/core/Mage/Sales/Model/Order/Item.php b/app/code/core/Mage/Sales/Model/Order/Item.php
index 388ce175ee1..1f7b2850449 100644
--- a/app/code/core/Mage/Sales/Model/Order/Item.php
+++ b/app/code/core/Mage/Sales/Model/Order/Item.php
@@ -236,7 +236,10 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_item');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'base_weee_tax_applied_row_amount' => 'base_weee_tax_applied_row_amnt',
+        ];
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Shipment.php b/app/code/core/Mage/Sales/Model/Order/Shipment.php
index 6cc30711603..724d52cb2d7 100644
--- a/app/code/core/Mage/Sales/Model/Order/Shipment.php
+++ b/app/code/core/Mage/Sales/Model/Order/Shipment.php
@@ -108,7 +108,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_shipment');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Quote.php b/app/code/core/Mage/Sales/Model/Quote.php
index 22c59fe8c46..8072e770879 100644
--- a/app/code/core/Mage/Sales/Model/Quote.php
+++ b/app/code/core/Mage/Sales/Model/Quote.php
@@ -208,7 +208,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('quote');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Quote/Address.php b/app/code/core/Mage/Sales/Model/Quote/Address.php
index e81d1709566..cede9cf2a96 100644
--- a/app/code/core/Mage/Sales/Model/Quote/Address.php
+++ b/app/code/core/Mage/Sales/Model/Quote/Address.php
@@ -231,7 +231,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('quote_address');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Quote/Item.php b/app/code/core/Mage/Sales/Model/Quote/Item.php
index 05e737e722d..e363f12103c 100644
--- a/app/code/core/Mage/Sales/Model/Quote/Item.php
+++ b/app/code/core/Mage/Sales/Model/Quote/Item.php
@@ -211,7 +211,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('quote_item');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/etc/config.xml b/app/code/core/Mage/Sales/etc/config.xml
index c83e510ade0..b62cf944a4e 100644
--- a/app/code/core/Mage/Sales/etc/config.xml
+++ b/app/code/core/Mage/Sales/etc/config.xml
@@ -1198,13 +1198,6 @@
             </product>
         </catalog>
         <sales>
-            <old_fields_map>
-                <order>
-                    <payment_authorization_expiration>payment_auth_expiration</payment_authorization_expiration>
-                    <forced_do_shipment_with_invoice>forced_shipment_with_invoice</forced_do_shipment_with_invoice>
-                    <base_shipping_hidden_tax_amount>base_shipping_hidden_tax_amnt</base_shipping_hidden_tax_amount>
-                </order>
-            </old_fields_map>
             <quote>
                 <totals>
                     <nominal>
diff --git a/app/code/core/Mage/Weee/etc/config.xml b/app/code/core/Mage/Weee/etc/config.xml
index af8fa12125b..7c9f74c1fdd 100644
--- a/app/code/core/Mage/Weee/etc/config.xml
+++ b/app/code/core/Mage/Weee/etc/config.xml
@@ -225,17 +225,6 @@
                     </weee>
                 </totals>
             </order_creditmemo>
-            <old_fields_map>
-                <order_item>
-                    <base_weee_tax_applied_row_amount>base_weee_tax_applied_row_amnt</base_weee_tax_applied_row_amount>
-                </order_item>
-                <invoice_item>
-                    <base_weee_tax_applied_row_amount>base_weee_tax_applied_row_amnt</base_weee_tax_applied_row_amount>
-                </invoice_item>
-                <creditmemo_item>
-                    <base_weee_tax_applied_row_amount>base_weee_tax_applied_row_amnt</base_weee_tax_applied_row_amount>
-                </creditmemo_item>
-            </old_fields_map>
         </sales>
     </global>
     <adminhtml>