nnmail expiry weirdness

[gyst@nfg.nl (Guido A.J. Stevens)]

Hi all,

I'm having a strange problem with mail expiry that I can't seem to
figure out for myself. Two groups with identical settings have
different expiry behaviour.

I'm using group parameters in topic mode to manage expiry. Gnus
pterodactyl 0.84.

I've got 2 nnml groups: "Personal" and "Subscriptions" in my root
topic "Gnus", which has topic parameters:

((expiry-wait quote never))

The groups themselves do not have any additional parameters. So I
would expect mail in both groups to not be expired. And since the
configuration of both groups is identical, they should behave
identically anyway.

Fact is, my personal mail does not expire, whereas my subscription
notices do. This is a PITA when you want to unsubscribe again, as you
can understand. More troublesome is the feeling that I don't have the
expiry under control, and the fear that one day some important emails
will get lost :-(.

The only difference I can see between the 2 groups, is that the
"Personal" group that doesn't get expired about always has some
articles ticked.

All my .gnus has to say about expiry:

;; If emacs is idle for an hour, expiry gets run. 
(gnus-demon-add-handler 'gnus-group-expire-all-groups nil 60)
;; But only delete mail which is explicitly expirable
(setq nnmail-expiry-wait 'never)

Does anybody have any clue what's going on here?

:*CU#
-- 
***    Guido A.J. Stevens      ***    mailto:gyst@nfg.nl    ***
***    Net Facilities Group    ***    tel:+31.43.3618933    ***   
***    http://www.nfg.nl       ***    fax:+31.43.3560502    ***   

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