function abrirPag(valor){
var url = valor;

xmlRequest.onreadystatechange = mudancaEstado;
xmlRequest.open("GET",url,true);
xmlRequest.send(null);

if (xmlRequest.readyState == 1) {
	var thediv=document.getElementById('displaybox');
	if(thediv.style.display == "none"){
		thediv.style.display = "";
	}
document.getElementById("displaybox").innerHTML = "<img src='load.gif'>";
}

return url;
}

function mudancaEstado(){
if (xmlRequest.readyState == 4){
	var thediv=document.getElementById('displaybox');
	if(thediv.style.display == "none"){
		thediv.style.display = "";
	}

document.getElementById("displaybox").innerHTML = xmlRequest.responseText;
}
}