So, from the server point of view, is it correct to send back an empty line if the Reply-To is not in the header, or should I try to deduce that info and send it to the client?
The Sender and Reply-To fields in the envelope must be filled in with the data from the From field by default.
-- Mark --
http://staff.washington.edu/mrc Science does not emerge from voting, party politics, or public debate. Si vis pacem, para bellum.