I just hit this on one of my lists, when someone tried to subscribe:

Bug in Mailman version 2.1.5a3

We're sorry, we hit a bug!

If you would like to help us identify the problem, please email a copy of this page to the webmaster for this site with a description of what happened. Thanks!

Traceback:

Traceback (most recent call last): File "/home/mailman/scripts/driver", line 87, in run_main main() File "/home/mailman/Mailman/Cgi/subscribe.py", line 96, in main process_form(mlist, doc, cgidata, language) File "/home/mailman/Mailman/Cgi/subscribe.py", line 176, in process_form mlist.AddMember(userdesc, remote) File "/home/mailman/Mailman/MailList.py", line 856, in AddMember self.HoldSubscription(email, name, password, digest, lang) File "/home/mailman/Mailman/ListAdmin.py", line 391, in HoldSubscription assert not self.__db.has_key(id) AssertionError

I updated to the latest cvs code, making sure this time to specify the maint tag I'd been forgetting, and installed, but make update tells me I'm trying to downgrade from 2.2 to 2.1.5a3, and that's probbaly not safe.. Did I end up hosing my listdb in my earlier upgrades?