diff -r 15bf7259bb7c -r d8a3531bc6b8 uiacceltk/hitchcock/coretoolkit/src/huicanvaswshwgc.cpp
--- a/uiacceltk/hitchcock/coretoolkit/src/huicanvaswshwgc.cpp	Tue Feb 02 07:56:43 2010 +0200
+++ b/uiacceltk/hitchcock/coretoolkit/src/huicanvaswshwgc.cpp	Mon Feb 22 17:57:49 2010 +0200
@@ -2067,7 +2067,8 @@
             TRgb oldColor = gc->PenColor();            
             gc->SetPenAlpha(0);
             gc->SetPenColor(KRgbBlue);
-            gc->Clear(); 
+            TRect rect = aUpdateRegion.BoundingRect();
+            gc->Clear(rect); 
             gc->SetPenAlpha(oldAlpha);
             gc->SetPenColor(oldColor);
             }
@@ -2106,6 +2107,7 @@
     // Set new clipping region which does not clip anything. 
     // We want always draw aUpdateRegion fully to the aRenderbuffer. 
     TRect displayArea = iCanvasGc->Gc()->DisplayArea(); 
+    
     iCanvasGc->Gc()->SetClip(displayArea); // this call does not transform region anymore
     
     // We use translation to get screen coordinates to match render buffer coordinates