diff -r 5ba07f7750a9 -r 57d26d31c595 uiacceltk/hitchcock/ServerCore/Src/alfhierarchymodel.cpp
--- a/uiacceltk/hitchcock/ServerCore/Src/alfhierarchymodel.cpp	Thu Sep 02 13:30:25 2010 +0300
+++ b/uiacceltk/hitchcock/ServerCore/Src/alfhierarchymodel.cpp	Tue Sep 28 14:40:28 2010 +0300
@@ -1070,7 +1070,7 @@
         // SetLayerUsesAplhaFlag is not supported for image visual
         node->Window()->SetLayerUsesAplhaFlag( enabled );
 #ifdef SYMBIAN_GRAPHICS_WSERV_QT_EFFECTS        
-        node->Window()->SetTransparencyAlphaChannel( enabled );
+        node->FlagChanged(MWsWindowTreeObserver::EAlphaChannelTransparencyEnabled, enabled);
 #endif // #ifdef SYMBIAN_GRAPHICS_WSERV_QT_EFFECTS        
         }
     else if( node ) // this would mean that node has being orphaneded but not yet deleted