SQL error after installing

I just intalled ACL and forum access on my Drupal 5 RC2 website.

I activated the modules, configured the forum. This all seemed to work fine. But when I logged out, I got this message:

* user warning: You have an error in your SQL syntax. Check the manual that corresponds to your MySQL server version for the right syntax to use near ' 1)) OR fa.tid IS NULL OR aclu.uid = 0) AND (t.tid IN (4, 0) OR query: SELECT t.* FROM term_node r INNER JOIN term_data t ON r.tid = t.tid INNER JOIN vocabulary v ON t.vid = v.vid LEFT JOIN forum_access fa ON t.tid = fa.tid LEFT JOIN acl acl ON acl.name = t.tid AND acl.module = 'forum_access' LEFT JOIN acl_user aclu ON aclu.acl_id = acl.acl_id AND aclu.uid = 0 LEFT JOIN term_data catd ON t.tid = catd.tid WHERE ((fa.grant_view >= 1 AND fa.rid IN (, 1)) OR fa.tid IS NULL OR aclu.uid = 0) AND (t.tid IN (4, 0) OR catd.vid NOT IN (4)) AND ( r.nid = 6 ) ORDER BY v.weight, t.weight, t.name in /www/htdocs/*edited*/helden/includes/database.mysql.inc on line 167.
* user warning: You have an error in your SQL syntax. Check the manual that corresponds to your MySQL server version for the right syntax to use near ' 1)) OR fa.tid IS NULL OR aclu.uid = 0) AND (t.tid IN (4, 0) OR query: SELECT t.* FROM term_node r INNER JOIN term_data t ON r.tid = t.tid INNER JOIN vocabulary v ON t.vid = v.vid LEFT JOIN forum_access fa ON t.tid = fa.tid LEFT JOIN acl acl ON acl.name = t.tid AND acl.module = 'forum_access' LEFT JOIN acl_user aclu ON aclu.acl_id = acl.acl_id AND aclu.uid = 0 LEFT JOIN term_data catd ON t.tid = catd.tid WHERE ((fa.grant_view >= 1 AND fa.rid IN (, 1)) OR fa.tid IS NULL OR aclu.uid = 0) AND (t.tid IN (4, 0) OR catd.vid NOT IN (4)) AND ( r.nid = 4 ) ORDER BY v.weight, t.weight, t.name in /www/htdocs/*edited*/helden/includes/database.mysql.inc on line 167.

This message appears for users who are NOT logged in. Once I am logged in with whatever user, I get no error message.