Re: [Exim] Temporary defer on callouts

On Sat, 2004-01-31 at 13:09 +0000, Ian A B Eiloart wrote:
> I'm not sure whether the RFC permits this, though. As I understand it, you
> must accept mail to postmaster, and to any known mailbox (but can reject
> mail addressed to a non-existant mailbox).

Although RFC2821 says you MUST send bounces with empty reverse-path, it
doesn't actually say you MUST accept them. You might be expected to
infer that for yourself in the general case though, given a modicum of
common sense.

OTOH in the absence of specific instructions to the contrary, it does
seem perfectly valid to refuse to accept mail with null reverse-path
even for known-valid addresses, _if_ it's known that those addresses
never send mail, and hence should never receive bounces.

Refusing to accept bounces to mailing lists, for example, does make a
lot of sense. Likewise for old email addresses which are forwarded to
current addresses only for backward-compatibility.

--
dwmw2