Leading not working

1

Can anyone tell me why leading will not work?? I’ve tried setTextFormat and setNewTextFormat and to no avail neither are working. Here is my function applying the new format.


function loadVideo(itemID)
{
	TweenMax.to(_parent.thumbwin,1,{_x:-800, autoAlpha:0, ease:Expo.easeOut});
	TweenMax.to(_parent.vidwin,1,{_x:2, ease:Expo.easeOut});
	var mc = _parent.vidwin;
	var flv = xml.firstChild.childNodes[itemID].attributes.flv;
	mc.ns.play(flv);
	var title = xml.firstChild.childNodes[itemID].childNodes[0].firstChild.nodeValue;
	var subtitle = xml.firstChild.childNodes[itemID].childNodes[1].firstChild.nodeValue;
	mc.titletxt = title;
	mc.subtxt = subtitle;
	
	//Set the format
	var my_fmt:TextFormat = new TextFormat();
	my_fmt.leading = -20;
	mc.title.autoSize = true;
	mc.vidwin.subtitle.autoSize = true;
	mc.title.setTextFormat(my_fmt);
}