" ... Is is possible for a list be modified to allow "firstname.lastname@example.org" to
send to the list but not be on the list of recipients, or be returned if a
"Who" command is done on the list? ..."
In your Majordomo lists directory, add a file (or create a list) called
"posters" (or call it whatever you'd like).
Put email@example.com in that file.
In your config file for the list to which you want firstname.lastname@example.org to be
able to post, add "posters" (or whatever you've named it) to the