Ah, I didn't look hard enough! In 3463, there's
X.6.3 Conversion required but not supported
The message content must be converted in order to be forwarded
but such conversion is not possible or is not practical by a
host in the forwarding path. This condition may result when an
ESMTP gateway supports 8bit transport but is not able to
downgrade the message to 7 bit as required for the next hop.
which seems about right.
On Sat, May 16, 2015 at 10:26 AM, Ned Freed
On the subject of smtp enhanced status codes, am I correct in
there is not currently a code for "mailbox does not accept binary
a la 5.6.7 for SMTPUTF8?
Not as far as I know. That said, while I understand that a mailbox matter
properly speaking, something that calls for a x.2.y code, it's not that
a stretch to have a mailbox issue manifest as a media incompatibility
In other words, I don't see why you just don't use 5.6.7 and be done with
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