function makeHttpRequest(url, callback_function, isGet, data, return_xml) 
{ 
    isGet = isGet == null ? true : isGet;
var http_request = false; 

if (window.XMLHttpRequest) { // Mozilla, Safari,... 
    http_request = new XMLHttpRequest(); 
    if (http_request.overrideMimeType) { 
	http_request.overrideMimeType('text/xml'); 
    } 
} else if (window.ActiveXObject) { // IE 
    try { 
	http_request = new ActiveXObject("Msxml2.XMLHTTP"); 
    } catch (e) { 
	try { 
	    http_request = new ActiveXObject("Microsoft.XMLHTTP"); 
	} catch (e) {} 
    } 
} 

if (!http_request) { 
    alert('Unfortunatelly you browser doesn\'t support this feature.'); 
    return false; 
} 
http_request.onreadystatechange = function()
{ 
    if (http_request.readyState == 4) { 
	if (http_request.status == 200) { 
	    if (return_xml) { 
		eval(callback_function + '(http_request.responseXML)'); 
	    } else { 
		eval(callback_function + '(http_request.responseText)'); 
	    } 
	} else { 
	    alert('There was a problem with the request.(Code: ' + http_request.status + ')'); 
	} 
    } 
} 
if(isGet){
    http_request.open('GET', url, true); 
    http_request.send(null); 
} else {
    http_request.open('POST', url, true); 
    http_request.setRequestHeader('Content-type','application/x-www-form-urlencoded');
    http_request.send(data); 
}
}