function controllaMail() {
	var nome = document.getElementById("nome");
	var cognome = document.getElementById("cognome");
	var mail = document.getElementById("mail");
	var tel = document.getElementById("tel");
	var ogg = document.getElementById("ogg");
	var msg = document.getElementById("msg");
	
	var flag = 0;
	for(var i=0; i<document.frm_mail.length; i++) {
		var tmp = document.frm_mail.elements[i];
		if(tmp.value == "") {
			tmp.style.backgroundColor = "yellow";
			flag = 1;
		}
	}
	
	if(flag == 1)
		return false
	else
		return true
}

function textChanged(textBox) {
	textBox.style.backgroundColor = "white";
}