Sorry this took so long to track down - but it was not a problem with the
conch-l list, and so took a bit more detective work.  The duplicate
messages are being posted to the list by a subscribers internet server (not
their own computer or email program - but the server they are using to
connect to the internet - in this case it was PI.NET).
 
For those who are interested here is the whole story.
We had to look at the complete email message headers which contain a list
of all the servers that 'handled' the messages.  Servers are multi-tasking
computers that listen for and are willing to pass along electronic
messages.  You do not see all of this information when you look at your
email messages because the programs we use on our local computers are set
to get rid of all of that extra header information that would take up a
page or two of our computer screen.  A message you send to the conch-l list
are passed along the internet from server to server until they reach their
final destination, the conch-l listserv server.  The server then runs the
message through filters to see if it is a spam, a repeat message, a message
that is too long, etc.  If it passes all the tests it is immediately sent
out to the list of conch-l subscribers (the listserv does not hold messages
to send out later unless our daily threshold is reached).  The re-posted
conch-l message headers don't match the previous ones.  Which is why the
Listserv's duplicates detector didn't catch them.  A server at PI.NET was
holding the messages, adding an additional entry to the header and
re-sending them.  Since the last duplicate post was a few days ago I
suspect that someone at PI.NET has figured out the problem and fixed it.
 
Amy
 
Amy Edwards, Program Coordinator ------ [log in to unmask]
 
Museum of Natural History        --------        phone (706) 542-4137
University of Georgia            --------            FAX 706-542-3920
Athens, GA 30602-1882       --------       http://museum.nhm.uga.edu/
-------------------------------------------------------------------
"A man's mind, stretched by new ideas, can never go back to its original
dimensions."             Oliver Wendell Holmes