[Logician]

not tested but should work:

edit functions.php, find:

PHP Code:

 if ($maxattachsize!=0 and $filesize>$maxattachsize) { 


REplace it as:

PHP Code:

 if ($maxattachsize!=0 and $filesize>$maxattachsize AND ($bbuserinfo[usergroupid]!=6 AND $bbuserinfo[usergroupid]!=5)) { 


find:

PHP Code:

global $safeupload,$tmppath, $allowduplicates, $allowimgsizefailure; 


and replace it as:

PHP Code:

global $safeupload,$tmppath, $allowduplicates, $allowimgsizefailure;
global $bbuserinfo; 


However please note that this still wont give mods or admins to upload attachmetns with unlimited sizes. There are PHP/MYSQL restrictions set in the PHP/MYSQL options in your server and you can not exceed these restrictions with coding in your scripts. Your host needs to change such settings to disable them.