Thanks, Mikko!
> I'm not sure but I suspect these might be caused by settings in the
> QMAILINJECT environment variable -- do you have that set? By default,
> qmail-inject (and thus, the sendmail wrapper) does not touch the From:
> header. It will also by default remove the Return-Path header but use
> the contents for the envelope sender. If you do have QMAILINJECT set,
> refer to the manual page again... Usually it doesn't need to be set,
> the defaults are good for most circumstances, so my first suggestion
> would be to unset it.
You guessed right! QMAILINJECT was indeed set, and it was set to `f'
(see the qmail-inject manpage for details :-). I commented it out and
all the trouble was gone. There's just the Return-Path left to the
MAILUSER and MAILHOST variables, but I don't care much about that. I
think I set QMAILINJECT when I followed some installation instructions
too blindly to know what I was doing.
Regards,
--
Matthias Lampert, Hamburg