It's my experience that it's not always -- or even mostly -- that
ISPs have changed the names, but that users change mail programs (for
instance, start using Netscape Mail) and inadvertently change the
return address when they configure it.  And I don't see how the
ALIASES NAMES list will help with this, since, I assume, you have to
know the address has been changed and add it to the list manually.
What usually happens on my lists is that someone suddenly discovers
she's unable to post (or, more likely, unable to unsubscribe) from
the invisibly altered address.

                                        -- Russ
                                __|~_
Russell A. Hunt            __|~_)_ __)_|~_           Aquinas Chair
St. Thomas University      )_ __)_|_)__ __)  PHONE: (506) 452-0424
Fredericton, New Brunswick   |  )____) |       FAX: (506) 450-9615
E3B 5G3   CANADA          ___|____|____|____/    [log in to unmask]
                          \                /
      ~~~~~~~~~~~~ http://www.StThomasU.ca/hunt/ ~~~~~~~~~~~~