Let's do some early tree pruning, else we will never get anywhere.
I propose that in the 822ext group that we limit our discussion to UA-level
acks (read acks) and to the format of ack messages in general, leaving a
placeholder for transport level acks in the ack message format. MTA-level
acks can be discussed in smtpext or elsewhere. I don't want to implement
MTA-level acks using UA-private data.
It may be that, like Nathaniel suspects, there isn't a lot of demand for
transport-level acks. That's fine, but I think the question of whether they
are useful is distinct from how they should be implemented, and that neither
one is appropriate for the 822ext (UA protocol) group.
Keith