function Controlla() {
	var re_emptyall = new RegExp("^[ ]*$");
	if ( (document.forms[1].username.value == "") || (re_emptyall.test(document.forms[1].username.value)) ) {
		alert("Per richiedere la tua password compila il campo Username");
		document.forms[1].username.select();
		return false;
	}
}