function enviaMail(){
var myConn = new XHConn();
if (!myConn) alert("XMLHTTP not available. Try a newer/better browser.");
var fnWhenDone = function (oXML) { document.getElementById('contenido_contacto').innerHTML = oXML.responseText+"<br/>"+document.getElementById('contenido_contacto').innerHTML; };
myConn.connect("../enviamail.php", "POST", "email="+document.getElementById('email').value+"&nombre="+document.getElementById('nombre').value+"&empresa="+document.getElementById('empresa').value+"&comentario="+document.getElementById('comentario').value, fnWhenDone);
}