Yes, the 7941 does support displaying the + character:
User Interface on IP Phones
Different types of IP telephones accept keypad input and present visual information in different ways. For purposes of this chapter only, we define the following phone types:
•Type-A phones — Include the Cisco Unified IP Phone 7905, 7912, 7940, and 7960.
•Type-B phones — Include the Cisco Unified IP Phone 7911, 7941, 7942, 7945, 7961, 7962, 7965, 7970, 7971, and 7975.
Support for + Dialing on the Phones
On Type-A and Type-B phones, it is not possible to dial a + sign using the keypad; however, on Cisco Unified Personal Communicator endpoints, the + sign may be typed in by the user using the computer's keyboard or entered as part of the input string when using a click-to-dial function of the endpoint.
On Type-A phones, there is no support to display the + sign.
On Type-B phones and on Cisco Unified Personal Communicator, incoming calls can present a calling party number including + as part of the number. When a call is offered to a phone, the number shown on the ringing phone is processed by any configured calling party number transformation patterns; however, the number stored in the missed and received calls directories is the original pre-transformation number, allowing the one-touch dialing of previously received calls featuring the + sign as part of the calling number.
