> I'm having a similar problem. I believe, the envelope thing
> might be the reason why I always have to approve messages
> to python-de@starship.python.net which were redirected form
> starship.skyport.net . Is it possible that there is some relay
> in the way which puts another envelope around the message?
> I'll give it a try.

I sent mail to Barry about this, but I'll share it for those
interested.  On my system (Linux 2.0.x, sendmail 8.9.3, 
procmail 3.12, and mailman 1.0b9), 

   sender = msg.GetEnvelopeSender()

sets sender to 'listname-admin@example.com'.  So something 
somewhere is changing the envelope address prematurely (it
should be changed *after* this function call).  syslog
verifies that the message is send from listname-admin
before pumping the message through

   '|$prefix/mail/wrapper mailowner listname'

But I don't understand why it's happening on certain systems and
not on others.

Chris