Index: DragOverTabControl.cs
===================================================================
--- DragOverTabControl.cs	(revision 13845)
+++ DragOverTabControl.cs	(working copy)
@@ -57,5 +57,13 @@
         SelectedIndex = tabIndex;
       }
     }
+
+    protected override CreateParams CreateParams {
+      get {
+        CreateParams cp = base.CreateParams;
+        cp.ExStyle |= 0x02000000;  // Turn on WS_EX_COMPOSITED
+        return cp;
+      }
+    }
   }
 }