Outlook keeps old computer name

[weber.randy]

SBS 2003, Exchange 2003, Outlook 2003.

I have a number of users who's email address shows up as follows:
New User <old computer name>

It shows up while typing the user into a new email message. It has
also showed up in email headers, though I can't seem to repeat that
part.

I know it has nothing to do with the NK2 because I created a new user
called Test and logged in as Test, then started outlook. As soon as I
sent one message to John Doe by choosing his name from the Global
Address book, the next time I typed John Doe, I see John Doe <old
Computer Name> in the To box.

Thanks in advance.

Randy Weber