I contact the user directly.  Here's the real problem *chuckle*:

My user is in the Navy, on a ship, floating (he wouldn't tell me where).
They have a computer server on the ship that makes contact with a satellite,
periodically.  When they lose contact, the server goes down and they all
lose that particular batch of e-mail (doesn't this just SOUND like a
government thing? :-)

Anyway, my user reassured me that it's a constant problem, there's nothing
anyone can do about it (so they've been told) and to just live with it.
Quite honestly, it's not a largescale problem for me (of the 100 or so
postings, per day, to my list, only 5-10 postings to him actually bounce).
So, for now, we'll let things go, and if I get an error message pertaining
to him, I'll simply delete it.

Thanks for your help, gang!

Blaine Thompson
Co-Owner - Sex-L