/**
* Processes a callback from payment gateway
*
* Success here doesn't mean the transaction was approved. It means
* the callback was received and processed without technical difficulties.
*
* @return Payment_Process2_Result instance on success, PEAR_Error on failure
* @todo Implement support for PayPal IPN???
*/
function processCallback()
{
$result =& parent::processCallback();
return $result;
}