Problems with QMail and Mailman

[bziuna]

Hi All,

each time a message is posted to my mailing list, the poster recieves following email:

> [email protected] schrieb am 04.02.05 12:40:10:
>
> Hi. This is the qmail-send program at p15176116.pureserver.info.
> I'm afraid I wasn't able to deliver your message to the following
> addresses. This is a permanent error; I've given up. Sorry it didn't
> work out.
>
> <[email protected]>:
> This message is looping: it already has my Delivered-To line. (#5.4.6)
>
> --- Below this line is a copy of the message.

The emailadress [email protected] is the address of the mailinglist.
The message goes through, so everything is fine... only this annoying message is a problem.

Any ideas how can I solve this problem?

Thanks
Maciej