[Mailman-Users] nodupes doesn't seem to be working with aliases

[Curtis Villamizar]

I'm not sure if this counts as suppressable dupes.  All users have
nodupes set.

  bin/export.py | grep nodupes | wc -l
       183
  bin/export.py | grep nodupes | grep -v True | wc -l
         0

I have a postfix virtual-alias of the form:

  a    b, c, d
  c    e, f
  d    g, h
  g    i, j
  h    k, l

If I send mail to a set of mailing lists then dupes get suppressed but
not if I send to an alias that expands to the same set of mailing
lists.  Mailman gets two copies from postfix but the message-id is the
same for both.  There is a to= and orig_to= in maillog but the
messages should be otherwise identical including the timestamps.

Is there a way to suppress dupes in this situation?

I have 5 such aliases for convenience but if I can't suppress dupes
its an annoyance since some people are on multiple mailing lists.  For
some reason I thought this used to work (but might have imagined it).

I'd rather not send a bunch of cross posted test messages, though if
more info is needed I can create some new "just for test" mailing
lists and aliases (on a just for test server if need be).

Curtis