how to avoid flikering button problem on Flash

From the earliest versions of Flash sometime we experienced this simple problem: - using MovieClips as Buttons and scaling them as rollover/rollout effect we got that ugly flickering effect.-
Today I read a very long tread about designers in serarch of some solution for this old issue. Since I didn't found an answer that satisfies me and since is really easy avoiding this problem I wrote this simple function:

function addButtonEvent(btn:DisplayObject):void {
 MovieClip(btn).buttonMode = true;
 MovieClip(btn).mouseChildren = false;
 var square:Sprite = new Sprite();
 square.graphics.beginFill(0x000000);
 var p = btn.getRect(btn.parent);
 square.graphics.drawRect(p.x, p.y, p.width, p.height);
 btn.parent.addChild(square);
 square.visible = false;
 MovieClip(btn).hitArea = square;
   
 btn.addEventListener (MouseEvent.MOUSE_OVER, blinkOver);
 btn.addEventListener (MouseEvent.MOUSE_OUT, blinkOut);
}
  
function blinkOver(e:MouseEvent = null) {
 Tweener.addTween(e.target, { scaleX:1.08, scaleY:1.08,time:.3 } );
}
  
private function blinkOut(e:MouseEvent  = null) {
 Tweener.addTween(e.target, {scaleX:1, scaleY:1,time:.1 } );
}

As you can see the tip is to create a static rectangle over the MovieClip and using it as hitArea.
You just need to call the addButtonEvent function in this way:

addButtonEvent(myMovieclip);

(super simple!!!) Note that for the scaling easing I used Caurina tweener