email addreses being replaced by ;

[andy]

Hi,
I have a user that when trying to reply to a certain message, all names
show up fine in th TO and CC filed but when she sends the email out, all
non-local users names get replaced by ; and it appear that the message is
never sent.
Any idea what might be causing the problem and how to make sure that the
email was actually sent out?
Outlook 2003 and exchange 2003.

Thanks