Mailman on 1and1 webhosting

I’m trying to setup a list serve using mailman with 1and1 everything except the webpages seems to work just fine.
I get this error when I try going to the mailman link.
“Bug in Mailman version 2.1.9

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. “