Sony DT360 - Manual (Page 57)

SECURITY
55
BusinessPhone 250 / BusinessPhone 50
Portable DT310 / DT360 / DT368
SECURITY
GENERAL
You can block your extension in order to prevent
unauthorized use of your telephone, e.g if your external calls
are placed on a specific account number.
BLOCK EXTENSION
Dial to block your extension
Verification tone, your extension is blocked.
Un-block extension
Dial to re-open
Dial your password and press to re-open
Verification tone, your extension is open for use.