Peter Marchert wrote:

You can use the program ContactMaker to create DistLists
automatically. The testversion is free and can be downloaded the
http://www.marchert.de

Hard to tell what that software will do when the web page is all in German.
While it may be able to scan multiple mail messages in a folder, pick out
all the sender addresses from those messages, and create a DL from that
list, who can tell?
--
Brian Tillman