Find "Call forwarding"
Press the phone icon.
Press the menu icon.
Press Settings.
Press Call settings.
Press GSM call settings.
Press Call forwarding.
Select divert type
The current settings are displayed.
Press one of the following options:
Always forward
Always forward
Forward when busy
Forward when unanswered
Forward when unreachable
Divert calls to voicemail
Key in (prefix) 5 (your phone number) and press ENABLE.
Return to the home screen
Press the Home key to return to the home screen.