Exim's rewriting of headers

[Johann Spies <jspies@sun.ac.za>]

I am user js on my computer and user jspies with email address
jspies@sun.ac.za on our network.

I have the following in my /etc/exim/exim.conf

*@bywoner jspies@sun.ac.za Ffrs				

Running exim -brw shows this:

zsh % sudo exim -brw root@bywoner
  sender: jspies@sun.ac.za
    from: jspies@sun.ac.za
      to: root@bywoner
      cc: root@bywoner
     bcc: root@bywoner
reply-to: jspies@sun.ac.za
env-from: jspies@sun.ac.za
  env-to: root@bywoner

So why do the headers look like this I send mail from the unix
commandline (mail jspies@sun.ac.za)?:

To: jspies@sun.ac.za
Subject: Toets mail
Message-Id: <E18mB0Q-0003Hh-00@bywoner>
From: Johann Spies <js@bywoner.sun.ac.za>
Date: Fri, 21 Feb 2003 13:06:14 +0200
Return-Path: js@bywoner.sun.ac.za

I suspect this is why my efforts to subscribe on some mailing lists
which request one to send an empty email so the list server failed in
the past because I did most of them from the command line.

Regards.
Johann
-- 
Johann Spies          Telefoon: 021-808 4036
Informasietegnologie, Universiteit van Stellenbosch

     "My sheep hear my voice, and I know them, and they 
      follow me; And I give unto them eternal life; and they
      shall never perish, neither shall any man pluck them 
      out of my hand."          John 10:27,28