Well I have been looking around and would this work?
in /include/class.ticket.php
Here: //Insert Staff Reply
function postResponse($msgid,$response,$signature='none',$attachment=false,$canalert=true){
global $thisuser,$cfg;
if(!$thisuser || !$thisuser->getId() || !$thisuser->isStaff()) //just incase
return 0;
$sql= 'INSERT INTO '.TICKET_RESPONSE_TABLE.' SET created=NOW() '.
',ticket_id='.db_input($this->getId()).
',msg_id='.db_input($msgid).
',response='.db_input(Format:($response)).
',staff_id='.db_input($thisuser->getId()).
',staff_name='.db_input($thisuser->getName()).
',ip_address='.db_input($thisuser->getIP());
$resp_id=0;
Should I add after created;
updated=NOW()