mailman issues ("We're sorry, we hit a bug!")

[Torbjorn Jansson]

Hello

Tried subscribing with a different email adress but all i got was this error 
from mailman:

Bug in Mailman version 2.1.29
We're sorry, we hit a bug!
Please inform the webmaster for this site of this problem. Printing of 
traceback and other system information has been explicitly inhibited, but the 
webmaster can find this information in the Mailman error logs or the web server 
logs.

got some advice?