On Mon, 2004-02-23 at 14:02 +0000, Nigel Metheringham wrote: > One wrinkle is that recipient callouts that use the originating sender
> can only be cached as a sender/recipient pair, so there may be rather
> more callouts than you expect.
Ouch. I hadn't thought of that. I'd be happy enough with using
postmaster@ for everything with non-empty reverse-path -- it'd at least
be better than <>.
If we just allow _recipient_ verification callouts to specify the MAIL
FROM address used, and cache appropriately, that should be fine.
I'd still refuse the requests to let _sender_ verification callouts
modify the address though.