In newthread.php and newreply.php, find this:
Code:
if ($bbuserinfo[userid]!=0 and time()-$bbuserinfo[lastpost]<=$floodchecktime and !ismoderator($foruminfo[forumid])) {
and replace it with this:
Code:
if ($bbuserinfo[userid]!=0 and time()-$bbuserinfo[lastpost]<=$floodchecktime and (!ismoderator($foruminfo[forumid] and $bbuserinfo[usergroupid]!=XXX))) {
Don't forget to chagne XXX to the ID of that usergroup!