Problem:
The PaReq returned for the cardsave gateway contains line breaks which when parsed through the ACSFrame form breaks the bank’s acs script.

Solution:
Replace the all line break instances within the PaReq from the returned cardsave gateway with a the ‘+’ character. i.e

// parse the cardsave gateway’s returned PaReq into the session
$_SESSION['PaREQ'] = $return['PaREQ'];

// replace the line break instances with ‘+’ character
$_SESSION['PaREQ'] = str_replace(” “, “+”, $_SESSION['PaREQ']);