function ajax(pagina,div){
	xmlhttp=new XMLHttpRequest();
	xmlhttp.onreadystatechange=function(){
		if (xmlhttp.readyState==4 && xmlhttp.status==200){
			document.getElementById(div).innerHTML=xmlhttp.responseText;
   		}
  	}
	
	xmlhttp.open("GET",pagina,true);
	xmlhttp.send();
	
}

if (window.XMLHttpRequest)
{
req = new XMLHttpRequest();
req.onreadystatechange = processReqChange;
req.open("POST",url,true);
req.send(null);
}
// Procura por uma versão ActiveX (IE)
else if (window.ActiveXObject)
{
req = new ActiveXObject("Microsoft.XMLHTTP");
if (req)
{
req.onreadystatechange = processReqChange;
req.open("POST",url,true);
req.send();
}
}