Have you actually removed that person from the DL and then added them back
to it? Try it if you haven't.

Yes I have tried that and it doesn't work. It's so strange because
when I am looking at the dialog that lists all of the contacts in the
distribution list (with the name in the left column and the email
address in the right column), it shows the old email address for the
contact. But if I double-click on the contact, so that it brings up
the dialog with all the info for the contact, it shows their new email
address. btw, I am using outlook 2002. Any other ideas? thanks