I can't find the original question but I did have an instance here where a
message kept running though the list. It ended up being an oversight on my
part. I had forgotten to create the '-owner' alias for the outgoing part
of the list. When we had one bad address in the list it got sent back to
the list-outgoing address and resent. This went on for 7 iterations before
I was able to kill the critter.
Computer Sciences Corporation