bug#30347: smtpmail.el doesn't retry with authentication when greylisting is used

[Lars Ingebrigtsen <larsi@gnus.org>]

Robert Pluim <rpluim@gmail.com> writes:

> Itʼs one of the ways. Some return 451 instead. Some 421. Itʼs all very
> fuzzy :-)
>
> Oh, and thereʼs an official 'authentication is required' code whose
> value escapes me for the moment.

Yeah, smtpmail just uses the "relay not permitted" codes to guess that
it's supposed to try again, which aren't exactly official, either.  So
adding 450/451/421, too, probably won't break anything.

> BTW, if emacs has credentials for the connection itʼs making, would it
> not make sense to attempt authentication before delivery?

You'd think so...  But this might lead to some annoyances in that people
have password-protected their password store, and will now be prompted
for that password even if the SMTP server doesn't require a password.

If you see what I mean.  :-)

So I'm not sure that change would be welcomed by everybody.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no