On Sat, 10 Mar 2001 22:46:00 -0800, Randy Ryan <[log in to unmask]> wrote:

>We have hit a very odd problem at the maelstrom listserv that I think is a
>bug and potentially a security problem.

It is a bug, but not with LISTSERV.  The mail goes to the RR server and is
'reflected' back with headers such as To: and From: unchanged.  In short it is a
mail loop due to mis-configuration or outright 'breakage' of the RR server.  The
only fix is to remove the subscriber address(s) at RR from your list (at least
set them to NOMAIL).  And probably turn on full confirmation for all posts byt
adding  ,confirm to whatever Send= is set to.  A pain and annoyance but very
effective at preventing duplicate posts and stopping mail loops.