Ive had this before damn memory onLoad issue

[mojito]

the following works outside of a class but I cant get the onLoad to fire another function inside the following class construct.

class Screen  {
	private var code:String;
	private var type:String;
	private var theme:String;
	private var title:String;
	private var xmlFile:String;
	private var dataXML:XML;
	//--------------------------------------------------------------
	public function Screen(code) {
		this.code = code;
		//trace("extended with CurrentPage");
		//trace("need to load the particular xml file here "+code+".xml");
		this.loadXML();
	}
	private function loadXML() {
		
		dataXML = new XML();
		dataXML.load("content/xml/"+this.code+".xml");
		dataXML.onLoad = function() {
			trace("loaded xml");

			this.toVars("test");
			// the XML is loaded so strip out the whitespace
			dataXML.ignoreWhite = true;
			// turn the XML doc content into flash variables
			
		};
	}/**/
	
	private function toVars(a){
		trace(">>"+a);
		//parse through the document and put our page into manageable object or arrays ?
		//how best to do this?
		//this is the parent class so is dealing only with screen based content.		
		}
}

toVars will not fire, despite the onLoad firing as it traces ok. I give the xml here

<menuroot>
    <node item="code" value="000000" />
    <node label="type" pos="contentTitle" />
	<node label="theme" pos="turqoiseBay" />
	<node label="content">
			<node item="title" value="<![CDATA[DISK OVERVIEW]]>" />
			<node label="graphic" pos="00000000.swf" />
	</node>
</menuroot>