About 17 people attended, including Stefan Schlott and Michael Feiri.
Talk + discussion from 20:00 till about 21:30.

Feedback given by CCC-Ulm audience:

Since signed S/MIME messages generally contain complete public key of
sender, use first post of sender to a list to collect key of sender.
No need for webui upload.  Generally, S/MIME users don't even know how
to save their public key in a file.

Generate list keypair on server; don't upload keypair of list via
webui.  Get rid of passphrase box in webui: don't use a passphrase (or
pinentry-stuff with gpg-agent, admin should give passphrase when
mailserver software starts up.) Passphrase-box was added since some pgp
libraries refuse to work with a passphrase-less key, in 2005.

S/MIME signed and encrypted messages are encrypted first, signature is
added to the encrypted stuff.  PGP messages are signed first, the
signed sttuff is encrypted.  So, SLS could keep the signature on
encrypted messages in the PGP-case.  This would make communication more
like end-to-end secure communication; one would make the system less
dependent on a trusted listserver.

Video of lecture like will get uploaded at about early february.