The mailing list for listmasters using Sympa

[Claus Atzenbeck <address@concealed>]

I just was experimenting with anonymous_sender parameter.
Two quesions on that:

1) Is it possible for the list owner or the listmaster to find out
from whom the message came from? If yes, how can they do that?

2) With this parameter is on, there is still a "X-Envelope-To" line in
the e-mail header which shows the sender's e-mail address; this is not
good for an anonymous message. (In my config file I have "send
privateorpublickey" -- maybe this has something to do with it!?)
How can I get rid of this line? Is it necessary? What is it doing?

Thanks a lot for your help!
Claus