Upgrade errors 6.0-6.1 in user.module and database.inc

Here's what I got after upgrading from 6.0 to 6.1

    * warning: array_fill() [function.array-fill]: Number of elements must be positive in <snip>/public/includes/database.inc on line 235.
    * warning: implode() [function.implode]: Invalid arguments passed in <snip>/public/includes/database.inc on line 235.
    * warning: array_keys() [function.array-keys]: The first argument should be an array in <snip>/public/modules/user/user.module on line 500.
    * 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 drupal_role r INNER JOIN drupal_permission p ON p.rid = r.rid WHERE r.rid IN () in <snip>/public/modules/user/user.module on line 500.

I replaced both those files with new ones from drupal 6.1, tried it again, and same error...any help??

Thanks in advance...here's my specs:

MySQL database 5.0.45
PHP 5.2.5
PHP memory limit 32M
PHP register globals Disabled
Unicode library PHP Mbstring Extension
Update notifications Enabled
Web server Apache