Hi if its cli you change it under the phone , just go down through the configuration mao against the mac address
http://www.cisco.com/c/en/us/support/docs/voice-unified-communications/unity-express/62609-tdcmecue.html#t18
Provision IP Phones
The Cisco Unified CallManager Express parameters are set so the IP phones can register and start to function. However, before you start to make and receive calls, you need to register the specific IP phones that you want on the Cisco CallManager Express system. In this process you set up individual ephone-dns and then associate each with a button or buttons on one or more ephones. Each ephone-dn is a virtual line, or extension, on which call connections can be made. Each physical phone must be configured as an ephone in the Cisco CallManager Express router in order to receive support in the LAN environment. With the use of the ephone-dn command and dual-line keyword you create an ephone-dn in dual-line mode. The reason is to have one voice port and two channels in order to handle two independent calls. This mode enables call transfer, call waiting, and conference options. This procedure registers ephones and ephones-dns with dual-line mode:
-
Enter the command enable in order to enter EXEC mode.
Router>enable
-
Enter the command configure terminal in order to enter the configuration mode.
Router#configure terminal
-
Enter the command ephone-dn dn-tag dual-line in order to create the extension with two channels.
Router(config)#ephone-dn 11 dual-line
-
Enter the command number number in order to configure a valid extension number.
Router(config-ephone-dn)#number 1001
-
Enter the command name name in order to associate a name to this ephone-dn.
Router(config-ephone-dn)#name John Smith
-
Enter the command exit in order to leave the ephone-dn configuration.
Router(config-ephone-dn)#exit
-
Enter the command ephone phone-tag in order to enter the physical phone configuration.
Router(config)#ephone 1
-
Enter the command mac-address [mac-address] in order to specify which phone is configured.
Router(config-ephone)#mac-address 0030.94C2.D6E7
-
Enter the command type phone-type in order to specify the type of phone.
Router(config-ephone)#type 7960
-
Enter the command button button-number (separator) dn-tag in order to associate the button number and line characteristics with an extension. In this case, use a :(colon) separator which implies a normal ring.
Router(config-ephone)#button 1:11
-
Enter the command end in order to finish the configuration.
Router(config-ephone)#end
