PHP Error by Distributed Authentification

Hi,

I've got a problem with my Drupal 5 installation. If a drupal.org user want to register at my site he got the following errors:

array_keys() [<a href='function.array-keys'>function.array-keys</a>]: The first argument should be an array in /.../modules/user/user.module in Zeile 361.
implode() [<a href='function.implode'>function.implode</a>]: Bad arguments. in /.../modules/user/user.module in Zeile 361.
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 &#039;)&#039; at line 1 query: SELECT DISTINCT(p.perm) FROM drupal_role r INNER JOIN drupal_permission p ON p.rid = r.rid WHERE r.rid IN () in /.../includes/database.mysql.inc in Zeile 167.

The authentification works an i found the user in my database. He also can work but got this three messages on register. Maybe a Bug?

Drupal 5.0
Cron-Wartungsaufgaben Zuletzt vor 28 Minuten 4 Sekunden ausgeführt
Dateisystem Beschreibbar (öffentliche Download-Methode)
Datenbankschema Aktuell
GD-Bibliothek 2.0 or higher
Konfigurationsdatei Geschützt
MySQL-Datenbank 5.0.22
PHP 5.1.2
Unicode-Bibliothek PHP mbstring-Erweiterung
Webserver Apache/2.0.55 (Ubuntu) PHP/5.1.2 mod_ssl/2.0.55 OpenSSL/0.9.8a

cu tb.