[Skylaw]

I have a '05 S-Class, and I believe our COMANDs are similar.

A review of my Operator's Manual and my COMAND manual indicate that pressing the "on hook" button on the steering wheel simply ends a call. Neither indicates that doing so during an incoming call will forward the call to voice mail.

Is it possible that the feature is one that is designed to function only on your phone (possibly set forth only in the telephone's own manual - you weren't specific about which you referred to) and not on COMAND?

My manuals indicate that some features are available from the phone, but not the steering wheel controls.

Also, you do not specify whether you have the earlier or later Bluetooth puck (the newer puck has part number B 6 7 87 5878). The later version integrated more phones than the earlier ones, and allowed more features in some cases.