Exchange Gateway and Appointments

[tmm]

Enviroment

GWISE 7.03 HF3, Exchange Gatway 7 SP2 HF1

MS Exchange 2003 SP2, MS Exchange 2007 SP1

All things work fine, but the problem is
if you send an request for an appointment from gwise to exchange it works, when the exhange user accept the appointment, gwise get an incoming message with "accepted", but the status of the clender will not be updated.

works this like defined or is this a bug ?
thomas