var xmlHttp = null;
var dataTXT = null;
var dataXML = null;
var callback = null

function callAjax(url, func){
	xmlHttp = null;
	callback = func;
	try {
		xmlHttp=new XMLHttpRequest(); // Firefox, Opera 8.0+, Safari
	} catch(e) {
		try {
			xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); // IE Method 1
		} catch(e) {
			xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); // IE Method 2
		}
	}
	if (xmlHttp==null) {
		alert ("Your browser does not support AJAX!");
	} else {
		xmlHttp.onreadystatechange = ajaxResults;
		xmlHttp.open("GET",url,true);
		xmlHttp.send(null);	
	}
}

function ajaxResults() {
   if(xmlHttp.readyState==4) {
		
        dataTXT = xmlHttp.responseText;
        dataXML = (xmlHttp.responseXML)? xmlHttp.responseXML.documentElement : null;
		callback(dataTXT, dataXML);
		
	// JS XML: dataXML.getElementsByTagName("")[0].childNodes[0].nodeValue;
   }
}