Public folder calendar

[shim]

When we attempt to add a public folder calendar to public folder favorites it
does not always link the same calendar, instead it creates a new blank
calendar.

Also, on the users that it does link to correctly it can take up to 1 minute
for any calendar entries / modifications to appear. Is there a setting in
Exchange where this rate rate can be increased?

All the users have the same permissions to the the calendar.
We are using Exchange 2003 & XP Pro client with Outlook 2003 Pro.

Any advice on the above would be greatly appreciated.

Thanks