Jeremy Harris <jgh(_at_)wizmail(_dot_)org> wrote:
On 08/02/2019 15:21, John R Levine wrote:
How reliably does that work? If I were writing an MTA I'd think a mix
of 2xx and 5xx is likely but 2xx and 4xx is unexpected.
Works fine with Exim; I'd call your MTA nonconforming if
if it didn't handle it.
There are situations where this can happen that are nothing to do with
disgusting filtering hacks :-) e.g. if the server is validating recipient
addresses and some of them depend on DNS lookups which fail.
f.anthony.n.finch <dot(_at_)dotat(_dot_)at> http://dotat.at/
Forties, Cromarty, Forth: South, veering west later, 6 to gale 8, perhaps
severe gale 9 later. Rough or very rough. Rain or showers. Good occasionally
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