Lock the keys and touch screen
To lock or unlock the touch screen and the keys, slide the lock
switch on the side of the device.
When the touch screen and keys are locked, the touch screen
is switched off and the keys are inactive.
The screen and keys may be locked automatically after a
period of inactivity. To change settings for automatic screen
and key locking, select
Menu
>
Settings
and
Phone
>
Phone mgmt.
>
Auto. keyguard
>
Keypad autolock
period
.