Can anyone tell me why this doesn't work? It does nothing and looks right to me???

Code:
home_btn.addEventListener(MouseEvent.CLICK, buttonClicked);
about_btn.addEventListener(MouseEvent.CLICK, buttonClicked);
portfolio_btn.addEventListener(MouseEvent.CLICK, buttonClicked);
contact_btn.addEventListener(MouseEvent.CLICK, buttonClicked);


function buttonClicked(e:MouseEvent):void
{
	switch (e.target)
	{
		case home_btn :
			MovieClip(parent).gotoAndStop("home");
			trace("home");
			break;

		case about_btn :
			MovieClip(parent).gotoAndStop("about");
			trace("about");
			break;

		case portfolio_btn :
			MovieClip(parent).gotoAndStop("portfolio");
			trace("portfolio");
			break;

		case contact_btn :
			MovieClip(parent).gotoAndStop("contact");
			trace("contact");
			break;
	}
}