Index: Patch.cs
===================================================================
RCS file: /cvsroot/wix/wix/src/wix/Patch.cs,v
retrieving revision 1.11
diff -u -r1.11 Patch.cs
--- Patch.cs	31 Oct 2008 09:13:17 -0000	1.11
+++ Patch.cs	8 Dec 2008 23:17:07 -0000
@@ -291,6 +291,15 @@
                     continue;
                 }
 
+                Table instanceTransformTable = mainTransform.Transform.Tables["WixInstanceTransforms"];
+                if (instanceTransformTable != null)
+                {
+                    foreach (Row r in instanceTransformTable.Rows)
+                    {
+                        productCodes[r[2].ToString()] = null;
+                    }
+                }
+
                 Table patchRefTable = patch.Tables["WixPatchRef"];
                 if (patchRefTable != null && patchRefTable.Rows.Count > 0)
                 {