Maybe that could help you, too? Do you get any PHP errors in PHP debug when you post something as a user and XOOPS is supposed to go through the notifications?
-tonsil
Fatal error: Cannot redeclare newbb_notify_iteminfo() (previously declared in C:\htdocs\main\modules\newbb\include\notification.inc.php:28) in c:\htdocs\main\modules\newbb\include\notification.inc.php on line 28
Notice [PHP]: Undefined index: nosmiley in file C:\htdocs\main\modules\newbb\post.php line 166
Notice [PHP]: Undefined index: icon in file C:\htdocs\main\modules\newbb\post.php line 167
Notice [PHP]: Undefined index: attachsig in file C:\htdocs\main\modules\newbb\post.php line 168