I (one of the manager of the EUnet-FR backbone machine: corton.inria.fr) would have been deeply flattered by Master400.it selecting us as their relay between SMTP and X.400 world (likely based on the excellence of our service). This choice would of course have led to some kind of 'contract', or at least minimum initial agreement; which we often accept in the context of EUnet to help connectivity.
Unfortunatly, no such agreement exist, nor any initial agreement have ever been made between Master400 and EUnet-FR; agreement which would have allowed us to set up the proper dedicated routes directing to Master400 once the mail is caught by the MX on corton.
I really should have guessed that. It's of course difficult for you to set up something you haven't been asked about and where no agreement exists. My apologies for indicating that this was a problem of yours. However, I think that some of the people receiving your message (and this) will feel a responsibility to contact the people administrating the x.400 service in Master400, Italy, to get the proper agreements in place, have the SMTP/ x.400 gateway configured accordingly and to complete the associated DNS registrations. Isn't it natural that the people behind domain@nis.garr.it take this ball? Regards, Havard