//ajax para navegacion por meses del calendario
function compruebaJS(hayJS) {
        var url = '/includes/functions/compruebaJS.php?hayJS='+hayJS+'&nocache=' + Math.random();
        if(window.XMLHttpRequest) {
                req = new XMLHttpRequest();
        } else if(window.ActiveXObject) {
                req = new ActiveXObject("Microsoft.XMLHTTP");
        }
        req.open("GET", url, true);
        req.onreadystatechange = callback_registro;
        if (req.overrideMimeType) { //Solo para noIE
			req.overrideMimeType('text/xml; charset=iso-8859-1');
		}
        req.send(null);
}

function callback_registro() {
        if(req.readyState == 4) {
                if(req.status == 200) {
                        response = req.responseText;
                        document.getElementById("REGISTROSINAJAX").innerHTML = response;
                } else {
                        alert("There was a problem retrieving teehe data:\n" + req.statusText);
                }
        }
}