Statistics stuck at 0

It's been a few days that we've installed Mollom to handle spam filtering for our forums. I don't see any errors anywhere, but the statistics show 0 spam and 0 ham, There has been some posts in our forums, though. The activation seemed fine, and the drupal admin shows:

Protect comment form YES
Protect user registration form YES
Protect user password request form YES
Protect blog entry form NO
Protect forum topic form YES
Protect page form NO
Protect story form NO

How can I check if mollom is working at all?

Actually, the logs do show

Actually, the logs do show errors. For every post there are two logs from mollom:

Mollom was unavailable (error: -13 - 13 Permission denied)
No Mollom servers could be reached or all servers returned an error -- the server list was emptied.

Now, I triple checked that the public/private key are correctly entered. Is there anything else I should do to activate the account?

Thanks!