How to get the real width of a button?

Example:

PHP Code:

---

var resetButton:Button = new Button();
resetButton.label = "Blabera Blub!";    
resetButton.move
(
   stage.width/2-resetButton.width/2,
   stage.height/2-resetButton.height/2
);
addChild(resetButton); 


---

Button always ends up slightly to the left.

If you want the actual width and height of the movie you need to write this:
stage.stageWidth/2+resetButton.width/2,
stage.stageHeight/2+resetButton.height/2

if you actually want to center your button then this is correct:
stage.stageWidth/2-resetButton.width/2,
stage.stageHeight/2-resetButton.height/2

Solved already. Code was ok, the way I nested it was not...