*** ADMIN: Strange "Sender" addresses on mailing lists

Folks:

Some of you may have noticed that every few messages that come from
midrange.com mailing lists have a strange sender address ... something
like...

midrange-l-bounces+david=fallingrock.net@midrange.com

This is called a VERP message ... VERP stands for "Variable Envelope
Return Paths".

VERP'ed messages let the mailing list software positively identify the
recipeient of a message that was bounced back to it.  Sometimes a mail
server will not include the same email address of the person a message was
sent to when it rejects a message (for whatever reason).

Since the recipient of the messages email address is encoded in the sender
address, when it gets bounced back, the mailing list software can
determine exactly who the message was sent to.  By doing so, it can
correctly remove subscribers whos email addresses are invalid.  This
reduces the load on the mail server and thus allows mailing list messages
to be delivered faster.

This only happens every 20 messages sent out by the list software.

If this is causing problems with filtering, please consider using a
different email header for filtering purposes ... the "X-List-Id" header
is defined in internet RFC's specificly for filtering purposes.

For more information on the VERP concept, please visit
http://cr.yp.to/proto/verp.txt

If you have any questions about this, please contact me privately.

david

-- 
"Who said I couldn't have it all?"
-B Gates