UBB.Developers Forums UBB.threads 7 Development How Do I? ERROR

I have installed ubb 6.04 and some hacks (whois online, avatar,...) ran the test file which approved of the paths and CHMODs. I can log in the control panel and am able to make modifications there. The weird thing is that i cant get in the forum, here is the error message:
Content-type: text/html
Software error:
Illegal division by zero at /home/cgi_bin/ubb_forum_summary.cgi line 114.
For help, please send mail to the webmaster ([email protected]), giving this error message and the time and date of the error.

Can anybody help me out?
Below are lines 113-115
# Calculate statistic data
$AverageTopics = sprintf("%.0f",$AllTopics / $AllForums);
$AveragePosts = sprintf("%.0f",$AllPosts / $AllForums);

Thanks in advance.

I don't those are the cause, since they are lines from the stock code. I'm pretty sure...Hmm..