Codice PHP:
if(mail("xxx@tin.it, [email]yyy@tin.it[/email]","email","Titolo: ".$gen."\nName: ".$_POST['contactname']."\naddress1: ".$_POST['address1']."\naddress2: ".$_POST['address2']."\ncity: ".$_POST['city']."\npostcode: ".$_POST['postcode']." \nphone: ".$_POST['phone']."\nemail: ".$_POST['email']."\nMessage: ".$_POST['enquiry']."\n","From: <".$_POST['email'].">\r\n"))  header('Location: conferma.html');  else echo "errore del server!"; 
hai provato così???