We are looking for a tool which modifies appointments (calender) in
Exchange 5.5 after activating daylight savings on the Exchange server
and on all client PCs.

History:
Many years ago we introduced Microsoft Exchange 5.0. Due to an error
in the german distribution Microsoft suggested to disable daylight
savings on server and clients. Now, 400 users created all their
appointments without daylight savings.

Our problem:
If we get appointments from external persons, time is shifted by one
hour. Additionally we get problems with some pda's, which don't allow
disabling daylight savings. That's why we want to enable daylight
savings. Unfortunately all appointments in summer time would shift by
one hour.

Example:
An appointment for 1. April 2004, 14:00 (summer time) was created on
1. March 2004 (winter time). Daylight savings was disabled.
Exchange/Outlook stores the following information: 12:00 GMT + 2:00
(German time zone) + 0:00 (no daylight savings) = 14:00 German time.
If we would enable daylight savings,  we would see 12:00 GMT + 2:00
(German time zone) + 1:00 (no daylight savings) = 15:00.

What we are looking for:
We would like to use a tool which modifies all time settings within
appointments according to appointment time and creation time. Any
ideas where we could get such a tool?

We are open for other suggestions as well.

Best regards
Chris