>>> Sadly Keith Moore's addrquery draft seems to have stalled: >>> >>> https://tools.ietf.org/html/draft-moore-email-addrquery-01 >Unfortunately, the draft is useless for end-to-end encryption, as it >relies on a clean path from the client to the recipient's SMTP server ... I would encourage anyone interested in this topic to read the draft, particularly section 4. No, it does not depend on a clean path from the MUA to the recipient MTA. R's, John