I wrote:

I have the sense that I am doing something very stupid, ...

Yep, I can answer now to my own stupid question. I had set my exim-configuration to do a "su" for every delivery for the analogs user. (Exim runs under "root" rigths.)

Thereby exim calls the mail-wrapper with mailman-rigths. After I have set the the "mail-gid" option to "mailman" it began to work.

:-)

But now I have an another problem...

:-(

regards Oliver