Got it all working (after some starting troubles) and happily surprised with
the results.
GW server is at office, GMS server at home.
Adding an appointment via Webacces at the GW server, is in seconds synced to
the GMS webpage.
And some seconds later displayed at my PDA.

But when I went on doing some testing. Mail and add calendar items.
I find "Folder is locked. Please try again later."
Trying again a few minutes later, same.

Anyone seen this?