Multiple warnings on node create

First of all, thanks for this module. I think this is really a missing core feature, so great this one exists for now. However, I get the following messages when I install/enable the module and make revlog mandatory for the book nodes. On book creation, I get:

* warning: array_fill() [function.array-fill]: Number of elements must be positive in /usr/local/www/sites/mysite/htdocs/drupal-6.17/includes/database.inc on line 253.
* warning: implode() [function.implode]: Invalid arguments passed in /usr/local/www/sites/mysite/htdocs/drupal-6.17/includes/database.inc on line 253.
* warning: array_keys() [function.array-keys]: The first argument should be an array in /usr/local/www/sites/mysite/htdocs/drupal-6.17/modules/user/user.module on line 513.
* 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 ')' at line 1 query: SELECT p.perm FROM role r INNER JOIN permission p ON p.rid = r.rid WHERE r.rid IN () in /usr/local/www/sites/mysite/htdocs/drupal-6.17/modules/user/user.module on line 513.

I have set no role to be able to skip revlog. When I disable revlog for this node type, the messages vanish. Any ideas? I could try the -dev but it looks like it's the same tarball, right?

Thanks for your help!
Stephan