trxn_result_code not stored in the financial_trxn table

trxn_result_code that is passed back in $params for payment processors is not being stored in the financial_trxn table. I have found that this is the case for the Realex payment process I am working on, but also noticed the following note in the Moneris.php

$params['trxn_result_code'] = (integer) $mpgResponse->getResponseCode();
// todo: above assignment seems to be ignored, not getting stored in the civicrm_financial_trxn table