[silin]

можно последить за нижним в MOUSE_MOVE

private var _prevHit:Boolean = false;		
private function onMouseMove(event:MouseEvent):void 
{
	var currHit:Boolean = downSprite.hitTestPoint(event.stageX, event.stageY, true);
	if (_prevHit != currHit)
	{
		currHit ? downOver() : downOut();
		_prevHit = currHit;
	}
}