Class problems with LoadMovie

programming flash
1

hi,
the only thing that this thing should do is to load a movie into a holder_mc and place it somewhere on the stage.
without a class it works.
within a class it does not.
why!? can anybody tell me please!


class Main extends MovieClip {
	var menuListener:Object;
	var menuLoader:MovieClipLoader;
	var menu_mc:MovieClip;
	var mcContent:MovieClip;
	//
	public function Main() {
		
		this.createEmptyMovieClip("menu_mc",  getNextHighestDepth());
		menuListener = new Object();	
		menuListener.onLoadInit = function(mcContent:MovieClip) {
			trace("hello world");
			mcContent._y = 515;
		};
		menuLoader = new MovieClipLoader();
		menuLoader.loadClip("ButtonMenu.swf", menu_mc);
		menuLoader.addListener(menuListener);

	}
}