I think one of the sites involved has a mailer which rewrites the 'Sender:' field to have an Internet-style address. The peering code in 1.7d can't handle that. With 1.7e mail is sent to peers via DISTRIBUTE, which bypasses the local mailer. The only solution I can offer right now is to send the beta 1.7e code to the site which rewrites the header, if they agree to run it. Eric