When desktop is shared through Office Communicator 2007 RibbonWindow is not repainting properly. The same issue can be reproduced through a remote desktop connection - when the RibbonWindow is running in a Aero Windows theme, the RibbonWindow chrome is painted in black when accessed through a remote desktop.
This is severely impacting our implementation. Very frustrating to our clients that we have to tell them that the toolkit we are using has this bug. This should get fixed.