Find "Fixed dialling numbers"
Press the menu icon.
Press Settings.
Press Call settings.
Press Fixed dialling numbers.
Change PIN2
Press Change PIN2.
Press the field below Old PIN2 and key in the current PIN2.
Press OK.
Press the field below New PIN2 and key in the new PIN2.
Press OK.
Press the field below Confirm new PIN2 and key in the new PIN2 again.
Press OK.
Exit
Press the Home key to return to standby mode.