Yealink SIP-T48G Administrator's Manual page 341

Parameters
Phone User Interface:
Menu->Features->Call Forward->No Answer Forward->On Code
forward.no_answer.off_code
Description:
Configures the no answer forward off code to deactivate the server-side no answer
forward feature. The IP phone will send the no answer forward off code to the server
when you deactivate no answer forward feature on the IP phone.
Example:
forward.no_answer.off_code = *77
Note: For Yealink IP phones (except SIP-T19(P) E2 and CP860), it works only if the
value of the parameter "features.fwd_mode" is set to 0 (Phone).
Web User Interface:
Features->Forward&DND->Forward->No Answer Forward->Off Code
Phone User Interface:
Menu->Features->Call Forward->No Answer Forward->Off Code
features.fwd_diversion_enable
Description:
Enables or disables the IP phone to present the diversion information when an
incoming call is forwarded to your IP phone.
0-Disabled
1-Enabled
Web User Interface:
Features->General Information->Diversion/History-Info
Phone User Interface:
None
forward.international.enable
Configuring Basic Features
Permitted Values Default
String within 32
Blank
characters
0 or 1
0 or 1
1
1
321