You can block certain types of calls such as incoming calls when you're abroad.
Find "Call Barring"
Press the menu icon.
Press Call settings.
Press Call Barring.
After a moment the current settings are displayed.
Select barring option
Press one of the following options:
Outgoing international roaming
Incoming international roaming
If you select Outgoing international roaming, no international calls can be made, but you can still call home when you're abroad. If you select Incoming international roaming, you can't receive incoming calls when you take your mobile phone abroad. Incoming calls will be rejected by the network and the call won't go through.
Activate or deactivate call barring
Key in your call barring password and follow the instructions on the display to activate or deactivate the function.
Return to the Home screen
Press the home icon to end the session and return to the Home screen.