ActionScript 3.0 :: How To Make Class To Manage XML File Configuration

I'm trying, without success, to make a class to manage a XML file configuration. This class has some methods to get a XML file and return a object E4X (XML) to user (programmer).

Then I created a package:
components.datahandlers
And the class to handler XML config file:
XMLConfigHandler.as

The code, that class, is below:
package components.datahandlers{
import flash.net.URLLoader;
import flash.net.URLRequest;
import flash.xml.XMLDocument;
import flash.events.*;
import flash.errors.*;
public class XMLConfigHandler {
[Code] .....

The trace above shows: NOT. But if I get a trace inside onLoaded method, it is show: YES. Why "xmlLoaded" property don't change to YES? How can I make this works?