var http_request = false;
	function makeRequest(parameters) {
		http_request = false;
		if (window.XMLHttpRequest) { // Mozilla, Safari,...
			http_request = new XMLHttpRequest();
			if (http_request.overrideMimeType) {
     			// set type accordingly to anticipated content type
				//http_request.overrideMimeType('text/xml');
				http_request.overrideMimeType('text/html');
			}
			} 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('Cannot create XMLHTTP instance');
				return false;
			}
			http_request.open('GET', parameters, true);
			http_request.onreadystatechange = function (){
					if (http_request.readyState == 4) {
						if (http_request.status == 200) {
							result = http_request.responseText;
							eval(result);
						} else {
							alert('Problemas con su solicitud.');
						}
					}
		}
		http_request.send(null);
	}