It appears that Sam Varshavchik <mrsam(_at_)courier-mta(_dot_)com> said:
A few months ago someone @icann.org contacted me regarding "UASG030 EAI
Testing Results for Courier". After swapping a few messages, the upshot was
that, apparently, the testing apparatus that was employed in that endeavor
expected SMTPUTF8 senders specify the UTF8 flag on anything that's sent to a
receiver that advertises SMTPUTF8, even if it's pure ASCII.
The person running the tests these days is me, and that's the exact
opposite of what the tests are looking for, that it *doesn't* send the
UTF8 flag on ASCII mail. I didn't run the tests on Courier, but I
think the people who did checked correctly.
By the way, last time I checked, when Courier adds a Received line it says
UTF8ESMTP rather than UTF8SMTP. Did you ever get around to fixing that? It
looks like a one or two line fix. Exim had the same bug.
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