try{
    xmlhttp = new XMLHttpRequest();
}catch(ee){
    try{
        xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    }catch(e){
        try{
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }catch(E){
            xmlhttp = false;
        }
    }
}  
function gotoURL(url,target){ //preenche os campos automaticamente
	document.getElementById('carregando').style.visibility='visible';
	xmlhttp.open("GET", url);
	xmlhttp.onreadystatechange=function() {
		if (xmlhttp.readyState==4){
			document.getElementById(target).innerHTML=xmlhttp.responseText;	
			document.getElementById('carregando').style.visibility='hidden';		
		}
	}
	xmlhttp.send(null);
}