/**
  * Sign this request message
  * .
  * @param string $privateKeyFile
  * @param string $privateKeyPassword
  */
 public function sign($privateKeyFile, $privateKeyPassword)
 {
     $values = $this->getSignValues();
     $message = implode('', $values);
     $sign = Pronamic_WP_Pay_Gateways_IDealAdvanced_Security::signMessage($privateKeyFile, $privateKeyPassword, $message);
     $this->merchant->tokenCode = base64_encode($sign);
 }