It appears that maybe the problem I was facing has been resolved. The
culprit? DSN settings in the MUA. The MUA was set to request a DSN in
case of delivery delays or failure, and this apparently somehow got
translated into a copy of the email being sent to the envelope sender.
Sorry for wasting everyone's time.
- --
Michael Kjörling, michael@??? -
http://michael.kjorling.com/
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