Does anyone know how to solve this error problem when clicking on the link to

"Tend to pending moderator requests"

resulting in the error message:

Bug in Mailman version 2.1.18-1 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.

My hosting provider cannot get me the log files, so hopefully there will be others who encountered this problem too.