public static function signup($username, $password, $email)
 {
     $md5password = md5($password);
     DalPCUser::addUser($username, $md5password);
     $uid = DalPCUser::insertID();
     DalPCUser::setUserInfo($uid, $email);
     MUser::persistentUserLogin($username, $md5password);
     return $uid;
 }