Package: mailman Version: 2.1.5-8 Yo!
The MIME parser mailman seems to do some header sanitizing, at least for message/rfc822 attachments. This is problematic as it breaks the PGP signature on the mail: My case: mail was multipart/signed [ text/plain message/rfc822 [ multipart/signed [ text/plain application/pgp-signature ] ] ] when it was fed to mailman. mailman of course wrapps that in multipart/mixed to add the unsubscribe instructions, and additionally breaks long header lines of the inner message/rfc822 (IIRC the outer headers where similarly sanitized, but as they're not signed it doesn't matter.) mailman has been identified as the culprit imho - I've sent a mail with the same structure over the same server, but directly to an account instead of mailman, and the signature arrived intact. greetings -- vbi -- get my gpg key here: http://fortytwo.ch/gpg/92082481
pgp3ueCycInmc.pgp
Description: PGP signature