onRelease event

Hey folks.

Im trying to load in some images from a xml-file, and make them into buttons (give them an onRelease function). I really had expected this to work, but apparently not. What am I doing wrong?

[AS]
var xml:XML = new XML();
xml.ignoreWhite = true;
xml.onLoad = function(){
var images:Array = xml.firstChild.childNodes;
for(var i=0;i<images.length;i++){
trace(images*.attributes.url);
holder = createEmptyMovieClip(“holder”+i, i);
holder._x = 5;
holder._y = 112i+5;
loadMovie(images
.attributes.url, holder);
trace(holder);
holder.onRelease = function(){
trace(“test”);
}
}
}
xml.load(“images.xml”);[/AS]