code: protected function _authenticateValidateResult($resultIdentity)
      {
          $code    = Zend_Auth_Result::FAILURE_CREDENTIAL_INVALID;
          $message = 'Supplied credential is invalid.';
  
          if (Benri_Util_String::verifyPassword($this->_credential, $resultIdentity[$this->_credentialColumn])) {
              $code             = Zend_Auth_Result::SUCCESS;
              $message          = 'Authentication successful.';
              $this->_resultRow = $resultIdentity;
          }
  
          $this->_authenticateResultInfo['code']       = $code;
          $this->_authenticateResultInfo['messages'][] = $message;
  
          /// _authenticateCreateAuthResult creates a Zend_Auth_Result object
          /// from the information that has been collected during the
          /// Benri_Auth_Adapter_DbTable::authenticate() attempt.
          return $this->_authenticateCreateAuthResult();
      }
docs: Attempts to make certain that only one record was returned in the
  resultset.
  
  @param array $resultIdentities
  @return Zend_Auth_Result
  @see http://framework.zend.com/manual/1.12/en/zend.auth.introduction.html#zend.auth.introduction.results Zend_Auth_Result