Calendar Color Labels Resetting

I have a user who is using Outlook 2003 on Exchange 2003. They are
using a public folder calendar and have changed the labels for the
colors.

They seem to stick on new events/appointments but after 2-4 new
appointments, they revert back to Outlook's defaults.

Any idea what might be causing this?

Also, since it is a public calendar, is there anyway for one person to
set up the labels and have the remaining users see the updated labels?
I assume it is user/machine specific but it sure would be nice to set
it up ahead of time.

Thanks very much in advance.

-dave