[Twisted-Python] (Mis)indented Posts (list administrativia)

[Jean-Paul Calderone]

On Fri, 3 Jul 2009 10:32:07 -0400, Gerrat Rickert <grickert at coldstorage.com> wrote:
>...ok, I've created a new post twice on this list twice, and both times
>my post has been indented and placed under a completely
>different/irrelevant post
>
>Here:
>http://twistedmatrix.com/pipermail/twisted-python/2009-June/019859.html
>And Here:
>http://twistedmatrix.com/pipermail/twisted-python/2009-July/019902.html
>
>...if this post hijacks a thread as well, then it will be 3 times.
>
>...this seems to be something specific to the twisted python mailing
>list:
>http://www.mail-archive.com/mailman-users%40python.org/msg53996.html
>

I don't really know much about how mailman generates those threaded views.
twisted-python is running on an unmodified mailman 1:2.1.9-9ubuntu1 install.
Perhaps this could be caused by exim4 configuration somehow (we do have
various exim4 configuration customizations), but that's the only thing I
can think of.  Any pointers on what information is used to determine the
threading structure of messages?

Jean-Paul