                 systemManager.getSandboxRoot().addEventListener(Event.RESIZE, systemManager_resizeHandler, false, 0, true);
             }
             
-            openButton.systemManager.getSandboxRoot().addEventListener(MouseEvent.MOUSE_WHEEL, systemManager_mouseWheelHandler);
+			if (openButton && openButton.systemManager)
+            	openButton.systemManager.getSandboxRoot().addEventListener(MouseEvent.MOUSE_WHEEL, systemManager_mouseWheelHandler);
         }
     }
     

        if (target)
        {
            // check if the target is the openButton or contained within the openButton
            if (openButton.contains(target))
                return true;
            if (hitAreaAdditions != null)
            {

                systemManager.getSandboxRoot().removeEventListener(Event.RESIZE, systemManager_resizeHandler);
            }
            
			if (openButton && openButton.systemManager)
            	openButton.systemManager.getSandboxRoot().removeEventListener(MouseEvent.MOUSE_WHEEL, systemManager_mouseWheelHandler);
        }
    } 
    
