diff --git a/mozilla/widget/src/windows/nsListBox.cpp b/mozilla/widget/src/windows/nsListBox.cpp
index 7419d01669e..ac82f13afba 100644
--- a/mozilla/widget/src/windows/nsListBox.cpp
+++ b/mozilla/widget/src/windows/nsListBox.cpp
@@ -291,4 +291,15 @@ DWORD nsListBox::WindowExStyle()
   return 0;
 }
 
+//-------------------------------------------------------------------------
+//
+// Clear window before paint
+//
+//-------------------------------------------------------------------------
+
+PRBool nsListBox::AutoErase()
+{
+  return(PR_TRUE);
+}
+
 
diff --git a/mozilla/widget/src/windows/nsListBox.h b/mozilla/widget/src/windows/nsListBox.h
index 564e2241bbd..308d01a0956 100644
--- a/mozilla/widget/src/windows/nsListBox.h
+++ b/mozilla/widget/src/windows/nsListBox.h
@@ -46,7 +46,7 @@ public:
     // nsIWidget interface
     BASE_IWIDGET_IMPL
 
-    // nsIListBox part
+    // nsIListBox interface
     void      SetMultipleSelection(PRBool aMultipleSelections);
     void      AddItemAt(nsString &aItem, PRInt32 aPosition);
     PRInt32   FindItem(nsString &aItem, PRInt32 aStartPos);
@@ -61,6 +61,9 @@ public:
     void      SelectItem(PRInt32 aPosition);
     void      Deselect() ;
     virtual   void      PreCreateWidget(void *aInitData);
+
+     // nsWindow interface
+    virtual   PRBool AutoErase();
 protected:
     PRBool  mMultiSelect;
     virtual LPCTSTR WindowClass();
diff --git a/mozilla/widget/src/windows/nsTextHelper.cpp b/mozilla/widget/src/windows/nsTextHelper.cpp
index e979f7aea41..0521e463993 100644
--- a/mozilla/widget/src/windows/nsTextHelper.cpp
+++ b/mozilla/widget/src/windows/nsTextHelper.cpp
@@ -168,4 +168,15 @@ DWORD nsTextHelper::WindowExStyle()
     return 0;
 }
 
+//-------------------------------------------------------------------------
+//
+// Clear window before paint
+//
+//-------------------------------------------------------------------------
+
+PRBool nsTextHelper::AutoErase()
+{
+  return(PR_TRUE);
+}
+
 
diff --git a/mozilla/widget/src/windows/nsTextHelper.h b/mozilla/widget/src/windows/nsTextHelper.h
index 85ea1d2e08f..6c5c687afeb 100644
--- a/mozilla/widget/src/windows/nsTextHelper.h
+++ b/mozilla/widget/src/windows/nsTextHelper.h
@@ -47,8 +47,8 @@ public:
     virtual PRUint32  GetCaretPosition();
     virtual LPCTSTR   WindowClass();
     virtual DWORD     WindowStyle();
-
-    virtual         void            PreCreateWidget(void *aInitData);
+    virtual void      PreCreateWidget(void *aInitData);
+    virtual PRBool    AutoErase();
 
 protected:
 
diff --git a/mozilla/widget/src/windows/nsWindow.cpp b/mozilla/widget/src/windows/nsWindow.cpp
index f6323e84b8d..ea2f15c000c 100644
--- a/mozilla/widget/src/windows/nsWindow.cpp
+++ b/mozilla/widget/src/windows/nsWindow.cpp
@@ -1078,10 +1078,13 @@ PRBool nsWindow::ProcessMessage(UINT msg, WPARAM wParam, LPARAM lParam, LRESULT
             result = OnKey(NS_KEY_DOWN, wParam);
             break;
 
-        // say we've dealt with erase background
-        case WM_ERASEBKGND:
-            *aRetValue = 1;
-            result = PR_TRUE;
+        // say we've dealt with erase background if widget does
+        // not need auto-erasing
+        case WM_ERASEBKGND:   
+              if (! AutoErase()) {
+              *aRetValue = 1;
+              result = PR_TRUE;
+            }
             break;
 
         case WM_MOUSEMOVE:
@@ -1709,5 +1712,10 @@ void nsWindow::AddEventListener(nsIEventListener * aListener)
   mEventListener = aListener;
 }
 
+PRBool nsWindow::AutoErase()
+{
+  return(PR_FALSE);
+}
+
 
 
diff --git a/mozilla/widget/src/windows/nsWindow.h b/mozilla/widget/src/windows/nsWindow.h
index a3641e5d269..7fb5f99061d 100644
--- a/mozilla/widget/src/windows/nsWindow.h
+++ b/mozilla/widget/src/windows/nsWindow.h
@@ -119,6 +119,7 @@ public:
             WNDPROC         GetPrevWindowProc() { return mPrevWndProc; }
 
     virtual PRBool          DispatchMouseEvent(PRUint32 aEventType);
+    virtual PRBool          AutoErase();
 
 protected:
 
diff --git a/mozilla/widget/tests/windows/winmain.cpp b/mozilla/widget/tests/windows/winmain.cpp
index 939eb1029d5..78ddff36fe0 100644
--- a/mozilla/widget/tests/windows/winmain.cpp
+++ b/mozilla/widget/tests/windows/winmain.cpp
@@ -77,7 +77,7 @@ char * gFailedMsg = NULL;
 #define WIDGET_DLL "raptorwidget.dll"
 #define GFXWIN_DLL "raptorgfxwin.dll"
 
-#define DEBUG_MOUSE 1
+#define DEBUG_MOUSE 0
 
 #define NUM_COMBOBOX_ITEMS 8
 #define kSetCaret        "Set Caret"