Meeting guest shown as meeting organizer

Here's an interesting issue that I wonder if anyone else
has experienced. I work in an office that uses an Exchange
2003 server and are a mix of PC and mac users. Our PC
users use Outlook XP and our Mac users use Outlook 2001
for Mac. We have a global address book set up which
includes distribution groups. We have a PC user who sent a
company-wide meeting request using a "Public" distribution
group and all the users must accept or decline this
meeting. However, we have one Mac user who whenever she
opens up the meeting request email, it shows that she is
the meeting organizer and she can not accept or decline
the meeting. Does anyone know what causes this or know how
to fix it? I have gone to this Mac user and the PC user
who sent the meeting request and both are doing the
correct things. FYI, all our Mac user opens up Outlook
2001 in OS 9.

Any insight would be greatly appreciated.

Thanks,
Lauren
..