[Mailman-Users] mailman 3.0 and exim

[Thomas Stein]

Hello.

Just installed mailman3 on one of my testsystems. There is only exim 
installed. No postfix. When i try to create a new list i get error 500 from 
nginx. The logfile says:

sh: /usr/sbin/postmap: No such file or directory
sh: /usr/sbin/postmap: No such file or directory
Traceback (most recent call last):
  File "/usr/lib64/python3.4/wsgiref/handlers.py", line 137, in run
    self.result = application(self.environ, self.start_response)
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/mailman/database/transaction.py", line 57, in wrapper
    rtn = function(*args, **kws)
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/mailman/rest/wsgiapp.py", line 65, in __call__
    environ, start_response)
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/falcon/api.py", line 182, in __call__
    responder(req, resp, **params)
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/mailman/rest/lists.py", line 207, in on_post
    mlist = create_list(**validator(request))
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/mailman/app/lifecycle.py", line 81, in create_list
    call_name(config.mta.incoming).create(mlist)
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/mailman/mta/postfix.py", line 69, in create
    self.regenerate()
  File "/home/mailman/mailman-bundler/venv-3.4/lib/python3.4/site-
packages/mailman/mta/postfix.py", line 104, in regenerate
    raise RuntimeError(NL.join(errors))
RuntimeError: command failure: /usr/sbin/postmap /home/mailman/mailman-
bundler/var/data/postfix_lmtp, 127, Key has expired
command failure: /usr/sbin/postmap /home/mailman/mailman-
bundler/var/data/postfix_domains, 127, Key has expired
[01/May/2015 04:14:48] "POST /mailman3/lists/new/ HTTP/1.0" 200 2716

Why is mailman looking for the postmap command? How can i prevent this from 
happening? 

thanks and cheers
t.