Common Area Phone and Call Forwarding

Hi,

Is it basicly possible to use Call Forwarding on Common Area Phones without Hot Desking?
According toTechnet yes. http://technet.microsoft.com/en-us/library/gg412807.aspx

We have a problem with the setup of Common Area Phones.

All CAP phones have a Voice Policy with Call Forwarding enabled and Firmware 4.0.7577.250. (Hard Reset done)
But the phone menu does not show the Call Forwarding entry.
When we log in as a user (Hot Desking) with the same Voice Policy, Call Forwarding is shown and functional.   

Any ideas?

Thank you in advanced for any input.

Cheers.
Dietmar