Xml function

I have written a xml function that I want to use wherever in the flash document I am and undepended of any objects and files. What have I done wrong? It don’t want to return the text.

function getXml(xname,xnr) {

xmlData = new XML();
xmlData.ignoreWhite = true;
xmlfile = global.xmldir + xname + "" + _global.lang + “.xml”;
xmlData.load(xmlfile);
xmlData.onLoad = function(success){
if (success){
xmltext = doc.childNodes[xnr].firstChild;
return xmltext;
}
}
return xmltext;
}