function sendRequest(url, callback, postData) {
	var req = createXMLHTTPObject();
	if(!req) {
		return;
	}
	
	var method = (postData) ? "POST" : "GET";
	
	req.open(method, url, true);
	req.setRequestHeader('User-Agent','XMLHTTP/1.0');
	
	if(postData) {
		req.setRequestHeader('Content-type','application/x-www-form-urlencoded');
	}
	
	req.onreadystatechange = function () {
		if(req.readyState != 4) {
			return;
		}
		
		if(req.status != 200 && req.status != 304) {
//			alert('HTTP error ' + req.status);
			return;
		}
		
		callback(req);
	}
	
	if(req.readyState == 4) {
		return;
	}
	
	req.send(postData);
}

var XMLHttpFactories = [
	function () {return new XMLHttpRequest()},
	function () {return new ActiveXObject("Msxml2.XMLHTTP")},
	function () {return new ActiveXObject("Msxml3.XMLHTTP")},
	function () {return new ActiveXObject("Microsoft.XMLHTTP")}
];

function createXMLHTTPObject() {
	var xmlhttp = false;
	for (var i = 0; i < XMLHttpFactories.length; i++) {
		try {
			xmlhttp = XMLHttpFactories[i]();
		}
		catch(e) {
			continue;
		}
		break;
	}
	return xmlhttp;
}

function randomQuestion(req) {
	var el = document.getElementById('span_randomQuestion');
	el.innerHTML = req.responseText;
}