warning for user which hasn't administer forums permissions

Hi!

I found a bug.
When User which hasn't administer forums permissions tries to add new forum topic,
a warning is presented:

warning: reset() [function.reset.html]: Passed variable is not an array or object in ....../drupal/sites/all/modules/og_forum/og_forum.module on line 712.
warning: key() [function.key.html]: Passed variable is not an array or object in ......./drupal/sites/all/modules/og_forum/og_forum.module on line 713.
warning: array_key_exists() [function.array-key-exists.html]: The first argument should be either a string or an integer in ........./drupal/sites/all/modules/og_forum/og_forum.module on line 714.

the reason is that in this case the "$the_rest->option" is not an array!!
What can I do?
How to solve it ?
Anybody????
I use Drupal 5.7.

thanks,
Miriam