[Mailman-Users] Mail bounces

[k.oliver at t-online.de]

Hello,
I installed the Debian packages Exim4 (v.4.5) and mailman (v.2.1.5) with
aptitude on Debian Sarge.

I configured Mailman for Exim according to
http://www.exim.org/howto/mailman21.html.

I set up a list called testlist and tried to post to the list from the
adiministrators e-mail account oliver at windfinder.com.

The emails bounce and this is the output from
my logfiles:
/var/log/mailman/smtp:
Nov 15 18:54:53 2005 (27329)
<mailman.6.1132077292.27327.testlist at server.windfinder.com> smtp for 1
recips, completed in 0.077 seconds

/var/log/mailman/vette:
Nov 15 18:54:52 2005 (27327) Message discarded, msgid:
<200511151854.13289.oliver at windfinder.com>

The list admin receives a mail with an "Auto-discard notification":
"The attached message has been automatically discarded."

Any ideas why? Thanks for your help.