function abrirPag(num,prod){

	nocache = Math.random();
	var url = 'qtds_creds.php?prod='+prod+'&num='+num+'&nocache='+nocache;
	//alert(url);

 set_xmlhttp();
	document.getElementById("qtds").innerHTML = '<img src="carr.gif" align="top" border="0" width="18" height="15">&nbsp;&nbsp;<font color="#9F1414"><b>Aguarde . . .</b></font>';
	xmlhttp.onreadystatechange = function() {
		if (xmlhttp.readyState == 4) {
			document.getElementById("qtds").innerHTML = xmlhttp.responseText;
		}
	}
	
	xmlhttp.open("GET", url, true);
	xmlhttp.send(null);

 }