/**
  * (non-PHPdoc)
  * @see Phoenix_WirecardCheckoutPage_Model_Abstract::getCustomerDob()
  */
 public function getCustomerDob()
 {
     $additionalInfo = $this->getInfoInstance();
     if ($additionalInfo->hasAdditionalInformation('wirecard_checkout_page_invoice_dob')) {
         $dob = $additionalInfo->getAdditionalInformation('wirecard_checkout_page_invoice_dob');
         if ($dob) {
             return new DateTime($dob);
         }
     } else {
         return parent::getCustomerDob();
     }
 }