function _doDebug($subject = 'PayPal debug data', $data, $useSession = true) {
    if (MODULE_PAYMENT_PAYPALWPP_DEBUGGING == 'Log and Email') {
      $data =  urldecode($data) . "\n\n";
      if ($useSession) $data .= "\nSession data: " . print_r($_SESSION, true);
      zen_mail(STORE_NAME, STORE_OWNER_EMAIL_ADDRESS, $subject, $this->code . "\n" . $data, STORE_OWNER, STORE_OWNER_EMAIL_ADDRESS, array('EMAIL_MESSAGE_HTML'=>nl2br($this->code . "\n" . $data)), 'debug');
    }
  }