[Mailman-Users] Mailman reusing message-id, leads to duplicate message suppression

[Ralf Hildebrandt]

Hi!

Mailman re-uses the message-id of the original email. In our case an
exchange user is recipient of two mailing-lists. Both mails are
adressed in the original message, both lists distribute the list, two
emails having the same message-id arrive at the Exchange server, which
seems to discard the second mail.

Who's to blame? Mailman for re-using the message-id? Exchange for
dropping the sencond mail on the floor?

Logs:


Mailman generates two mails (note the different Subject: lines):

Nov  5 07:22:47 webmail postfix/cleanup[14648]: CE5BB4C80: warning: header Subject: [Rundmail Virchow-Klinikum] Nervenarztpokal from localhost.localdomain[127.0.0.1];
from=<rundmail-neuro-cvk-bounces+annette.schxxxxxxxx=charite.de at charite.de>
to=<annette.schxxxxxxxx at charite.de> proto=ESMTP helo=<webmail.charite.de>

Nov  5 07:22:50 webmail postfix/cleanup[14650]: 1165D4E03: warning: header Subject: [Rundmail MITTE] Nervenarztpokal from localhost.localdomain[127.0.0.1];
from=<rundmail-neuro-ccm-bounces+annette.schxxxxxxxx=charite.de at charite.de>
to=<annette.schxxxxxxxx at charite.de> proto=ESMTP helo=<webmail.charite.de>

and sends them (note the identical message-id in the 250 2.6.0
response):

Nov  5 07:23:29 webmail postfix/smtp[14564]: CE5BB4C80: to=<schxxxxx at exchange.charite.de>, orig_to=<annette.schxxxxxxxx at charite.de>,
relay=s-mx14-ht01.charite.de[10.32.37.105]:25, delay=41, delays=0/39/0.05/2.1, dsn=2.6.0, status=sent (250 2.6.0
<0CFDA44554AB664BB2CAD4064F9C5B409C1C2F331A at EXCHANGE41.charite.de>
[InternalId=22196600] Queued mail for delivery)

Nov  5 07:23:48 webmail postfix/smtp[14576]: 1165D4E03: to=<schxxxxx at exchange.charite.de>, orig_to=<annette.schxxxxxxxx at charite.de>,
relay=s-mx14-ht01.charite.de[10.32.37.105]:25, delay=58, delays=0.01/55/0.06/3.4, dsn=2.6.0, status=sent (250 2.6.0
<0CFDA44554AB664BB2CAD4064F9C5B409C1C2F331A at EXCHANGE41.charite.de>
[InternalId=22196727] Queued mail for delivery)

Exchange only delivers one (the first) to the user's mailbox.

-- 
Ralf Hildebrandt                   Charite Universitätsmedizin Berlin
ralf.hildebrandt at charite.de        Campus Benjamin Franklin
http://www.charite.de              Hindenburgdamm 30, 12203 Berlin
Geschäftsbereich IT, Abt. Netzwerk fon: +49-30-450.570.155