PSÂ Sorry for the delay; I went through three (VPS) servers and wrestled with a variety of copies of Mailman 3 before deciding that Discourse was a better option.
sam... i, ah... i've been running debian, exim4, mailman, fail2ban, greylistd, virtual domains, and at one point even integrated with cyrus2.2, running my mail server now continuously since 2006, and i didn't have any difficulties at all following the instructions on how to set up mailman with debian and exim4.
if i may be... ah... how can i put this... email sysadmins "giving up" on setting up a mailing list and setting up a *forum* instead, has me concerned.
my (extensive) group project management experience immediately leads me to ask: where is the wiki which describes the (full) setup on the fosdem servers (including the config files), so that they can be reviewed, commented on, suggestions made, and improvements discussed?
also, has a staging server been set up so that modifications can be tested out prior to going live?
l.