function ajaxCheckUniqLogin($vars)
 {
     $login = htmlentities($vars['login']);
     $msg = null;
     do {
         // check for valid login first
         if ($vars['login'] == '' || strlen($vars['login']) < $this->getDi()->config->get('login_min_length', 1) || strlen($vars['login']) > $this->getDi()->config->get('login_max_length', 64)) {
             $msg = sprintf(___('Please enter valid Login Name. It must contain at least %d characters'), $this->getDi()->config->get('login_min_length'), $this->getDi()->config->get('login_max_length'));
             break;
         }
         if (!preg_match($this->getDi()->userTable->getLoginRegex(), $vars['login'])) {
             $msg = $config['login_disallow_spaces'] ? ___('Username contains invalid characters - please use digits, letters or spaces') : ___('Username contains invalid characters - please use digits and letters');
             break;
         }
         // check if it is available
         $r = UserTable::checkUniqLoginPassEmail($vars['login'], $vars['email'], $vars['pass']);
         if (!$r) {
             $msg = sprintf(___('Username %s has been taken by another user'), htmlentities($login)) . ".<br />" . ___('Please select a different log-in name') . "<br />" . sprintf(___('If that is your account, please go to %syour membership page%s to login into your subscription.'), "<a href='member' target='blank'>", "</a>");
             break;
         } else {
             $msg = true;
             break;
         }
     } while (false);
     return $this->ajaxResponse($msg);
 }