Find "Voice call"
Press Applications.
Press Settings.
Press Call.
Press Call forwarding.
Press Voice call.
Select divert type
The current settings are displayed.
Press one of the following options:
Always forward
Always forward
Forward when busy
Forward when unanswer
Forward when unreachab
Divert calls to voicemail
Key in (prefix) 5 (your phone number) and press Enable.
Exit
Press the Home key to return to standby mode.