function makeHttpRequest(url, callback_function, return_xml) {
	
	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) {
					if (callback_function != '') {
						eval(callback_function + '(http_request.responseXML)');
					}
				} else {
					if (callback_function != '') {
						eval(callback_function + '(http_request.responseText)');
					}
				}
			} else {
				alert('There was a problem with the request.(Code: ' + http_request.status + ')');
			}
		}
	}
	http_request.open('GET', url, true);
	http_request.send(null);
}