有關CREATE BOOKS CHILD PAGE的問題

大家好！！

我用的是PHP5.2, APACHE2.2, MYSQL 5.0 和DRUPAL 4.7. 當我嘗試CREATE BOOK的時候，沒有任何問題。但當我想CREATE CHILD PAGE時，就出現了以下的一段錯誤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 ') AND ou.mail_type=1' at line 1 query: SELECT DISTINCT(u.mail) as mail, ou.nid AS gid, n.title AS group_name, n.uid AS group_uid, u.name AS group_owner FROM og_uid ou INNER JOIN users u ON ou.uid=u.uid INNER JOIN node n ON ou.nid=n.nid WHERE ou.nid IN () AND ou.mail_type=1 in D:\Apache\htdocs\includes\database.mysqli.inc on line 121.

但那個CHILD PAGE是能夠CREATE到的，也可以進行操作，這是為什麼呢？
謝謝各位！！

Cyrus