         
         // We want to prevent the default down behavior for back key if 
         // the navigator has a view to pop back to
-        if (key == Keyboard.BACK && canCancelBackKeyBehavior)
-            event.preventDefault();
+        if (key == Keyboard.BACK)
+        {
+            backKeyEventPreventDefaulted = event.isDefaultPrevented();
+            
+            if (canCancelBackKeyBehavior)
+                event.preventDefault();
+        }
     }
     
     /**

    private function deviceKeyUpHandler(event:KeyboardEvent):void
    {
        var key:uint = event.keyCode;
        
        if (key == Keyboard.BACK && canCancelBackKeyBehavior)
            backKeyHandler();
    }
    

    {
        super();
    }
    
    //--------------------------------------------------------------------------
    //
    //  Variables
    //
    //--------------------------------------------------------------------------
    
    /**
     *  @private
     *  This flag indicates when a user has called preventDefault on the
     *  KeyboardEvent dispatched when the back key is pressed.
     */
    private var backKeyEventPreventDefaulted:Boolean = false;
    
    //--------------------------------------------------------------------------
    //
