Samsung SGH-P735MSATMB - Manual (Page 141)

Settings
140
PIN Check
When the PIN Check feature is enabled, you must enter your
PIN each time you switch on the phone. Consequently, any
person who does not have your PIN cannot use your phone
without your approval.
Note: Before disabling the PIN Check feature, you must enter your
PIN.
The following options are available:
Disable: the phone connects directly to the network when you
switch it on.
Enable: you must enter the PIN each time the phone is
switched on.
Change PIN
This feature allows you to change your current PIN to a new
one, provided that the PIN check feature is enabled. You must
enter the current PIN before you can specify a new one.
Once you have entered a new PIN, you are asked to confirm it
by entering it again.
Phone Lock
When the Phone Lock feature is enabled, the phone is locked
and you must enter 4 to 8-digit phone password each time the
phone is switched on.
The password is preset to “00000000” at the factory. To change
the phone password, see the Change password menu (Menu
9.6.4).
Once the correct password has been entered, you can use the
phone until you switch it off.