i thoght a little about the majordomo aspect of your work.
i understand that your main problem with this was conceptual
rather than technical.

the way i imagine this effort as follows:

- this is not a tango interactive module. rather, it should be a tool
  for system administrator enabling quick setup of the majordomo
  lists for communities.

- our PIM (personal identity module) assumes that we use an RDBMS
  to setup a database of tango users. part of this process is a setup
  of communities supported by a collection of servers.

- at present, there is no integrated tool to setup a majordomo list if
  a community is defined in PIM. it is required that every community
  has such a list.

  we hence seek a methodology to ensure that shall a community be
defined,
  a procedure will be started to set up a respective list. further,
every time
  a user decides to join a community, s/he should automatically join the
list.

- to accomplish this, we need a software module that, when called from
PIM,
  will set the list and/or add/remove users.

  how do we do that? how about the following scheme:

- we write a set of shell scripts that a) setup new majordomo list on a
designated
  server (server name should be a cobnfigurable parameter);  b) maintain
a master
  list of the lists that must be consistent with the list of communities
in the PIM
  database; c) when a user is supposed to be added/removed, the scripts
send
  messsages to majordomo to get it done; d) on request, the scripts
retrieve
  actual user lists from majordomo and return it to PIM to enable
consistency
  checks; e) scripts implement logic to analyse mail responses from
majordomo
  to be able to find out if operations (c) were effectively carried out

  i imagine that the scripts would run under a special UNIX user who
would own
  the lists and to whom majordomo would return emails.

  the entire thing could be implemented as servlet, but this may be an
overkill.
  a good old cgi-bin may be a way to go. in either case PIM would invoke
the scripts
  as URLs

- on the tango site, the functionality is trivial: any mail send to or
by a user is cc-ed to
  the user's current community majordomo list

i consider this to be quite an important, if seemingly simple project

marek