Gnus/nnimap + Debian Courier-IMAP = not uidvalid

[Kevin Hilman <kevin@hilman.org>]

I'm running Debian 'testing' with Courier IMAP and Gnus v5.9.0.  The
basic problem is that every time a new mail arrives (or I move mail
from one IMAP folder to another) the folder(s) become not uidvalid.

Doing a M-c and G-p (and removing the uidvalidity number) makes it
work again until the next time I get a message.

I used a Gnus v5.8.8 to connect to the same IMAP server and got the
same results.  I'm sucessfully using gnus-5.8.8/nnimap at work to
connect to a Lotus IMAP server, so I'm starting to suspect something
on the courier side.  However, I can use Evolution or Mozilla IMAP
clients to connect to this courier server without any issues.

As a (temporary) workaround I tried nnmaildir and can use it to
directly read the maildirs that qmail creates (and which courier
reads) and that works without any problems, but I'd prefer to get the
nnimap working since the Gnus won't always be running on the system
with the local maildirs.

Any assistance would be appreciated,

--
Kevin Hilman
Seattle, WA