diff --git a/generic/tkInt.h b/generic/tkInt.h
index 76c1dcdf8..d4d677d7b 100644
--- a/generic/tkInt.h
+++ b/generic/tkInt.h
@@ -1095,10 +1095,10 @@ typedef struct TkpClipMask {
 #endif
 
 #ifndef Button6Mask
-# define Button6Mask (1<<13)
+# define Button6Mask (AnyModifier<<6)
 #endif
 #ifndef Button7Mask
-# define Button7Mask (1<<14)
+# define Button7Mask (AnyModifier<<7)
 #endif
 #ifndef Button8Mask
 # define Button8Mask (AnyModifier<<4)