>> Section 4.1.1.2 additionally states that "The reverse-path consists of >> the sender mailbox", not a variation thereof. That wording apparently >> bans using time-varying tags ...
>OK, I have to admit I hadn't thought of or noticed this conflict. As >a practical matter there are already an abundance of schemes that >violate the letter, if not the intent, of this language: SRS and VERP >immediately come to mind. I therefore wonder if this isn't something >we ought to consider "relaxing" in 2821bis. I don't get how it's a conflict. It doesn't say that mailboxes have to be unique or have to be valid forever. Section 2.3.10 roughly says that a mailbox is a thing that can receive mail, but it doesn't say that it has to be able to receive mail a year from now, and it also doesn't preclude having a thousand different addresses that happen to deliver to the same place. I don't see how that contstrains the address beyond requiring that it can accept a bounce. In 2821bis the argument to MAIL FROM is a reverse-path which is "the source mailbox ... which can be used to report errors". The definition of mailbox is now section 2.3.11 but the wording is the same. Again, I don't see how that contstrains the address beyond requiring that it accept bounces. If the bounce address weren't valid at all, or it deliberately stopped working in 20 minutes, that could reasonably be said not to comply, but the intent with the BATV timestamps is that the addresses will remain valid at least for the week during which the message might be retried and bounces sent. R's, John
