Could it be here in class.ticket.php
function update($var,&$errors) {
global $cfg,$thisuser;
$fields=array();
$fields = array('type'=>'string', 'required'=>1, 'error'=>'Name required');
$fields = array('type'=>'email', 'required'=>1, 'error'=>'Email is required');
$fields = array('type'=>'text', 'required'=>1, 'error'=>'Reason for the update required');
$fields = array('type'=>'string', 'required'=>1, 'error'=>'Subject required');
$fields = array('type'=>'int', 'required'=>0, 'error'=>'Invalid Selection');
$fields = array('type'=>'int', 'required'=>0, 'error'=>'Invalid Priority');
$fields = array('type'=>'phone', 'required'=>0, 'error'=>'Valid phone # required');
$fields = array('type'=>'date', 'required'=>0, 'error'=>'Invalid date - must be MM/DD/YY');
if(!$errors){
$sql='UPDATE '.TICKET_TABLE.' SET updated=NOW() '.
',email='.db_input($var).
',name='.db_input(Format:($var)).
',subject='.db_input(Format:($var)).
',phone="'.db_input($var,false).'"'.
',phone_ext='.db_input($var?$var).
',priority_id='.db_input($var).
',topic_id='.db_input($var).
',duedate='.($var?db_input(date('Y-m-d G',Misc:($var.' '.$var))):'NULL');
if($var) { //We are setting new duedate...
$sql.=',isoverdue=0';
}