Here goes (yep, we're using 1.18 - our production server didn't like 1.17):

GT::SQL::error = Failed to prepare query: '
SELECT *
FROM gforum_Post LEFT OUTER JOIN gforum_User ON gforum_Post.user_id_fk = gforum_User.user_id

ORDER BY post_replies DESC ' Reason: ORA-00933: SQL command not properly ended (DBD ERROR: OCIStmtExecute/Describe)