public function addUser($user,$pass) {
    if(!empty($user) && !$this->userExists($user) && !empty($pass)) {
      array_push($this->htpwd,$user.':'.crypt($pass,substr(str_replace('+','.',base64_encode(pack('N4', mt_rand(),mt_rand(),mt_rand(),mt_rand()))),0,22)));
      $this->_save();
      return true;
    } else {
      return false;
    }
  }