Todd A. Jacobs wrote: > The question of whether a challenge is legitimately a bounce message is > probably worth discussing. > > Certainly, from a smarthost's perspective it > isn't, as it isn't part of an SMTP transaction.
That shouldn't be true; there's nothing in SMTP that requires a bounce be generated solely in the context of the SMTP transaction that is receiving the message being bounced. In fact, it's not actually even possible; even in the situation where an SMTP server refuses to accept a message whilst it's being received (which would seem to satisfy the situation you're alluding to), the sending MTA isn't operating in the context of any inbound SMTP transaction, and it's the sending MTA that's generating the bounce message. In other words, bounce messages are always generated as a new SMTP/... transaction by the bouncing MTA, not inline in the existing SMTP connection when a message is being rejected. As other examples, consider MTAs such as qmail that only bounce messages due to invalid recipient addresses well after accepting the message for delivery. Or, consider MTAs that retry delivery a number of times for perhaps a few hours before giving up (e.g. due to over-quota, bad .forward scripts, etc.). _____________________________________________ tmda-users mailing list (tmda-users@tmda.net) http://tmda.net/lists/listinfo/tmda-users
