Hi Sunish,

Maybe this is what you are after :)

To use a PIN code to authorize calls (like FAC codes in CCM). In CME use Call Blocking and Override funtionality. Have a look;

Call blocking to prevent unauthorized use of phones is implemented by matching a pattern of specified digits during a specified time of day and day of week or date. Up to 32 patterns of digits can be specified. Call blocking is supported on IP phones only and not on analog foreign exchange station (FXS) phones.

When a user attempts to place a call to digits that match a pattern that has been specified for call blocking during a time period that has been defined for call blocking, a fast busy signal is played for approximately 10 seconds. The call is then terminated, and the line is placed back in on-hook status.

Call blocking applies to all IP phones in a Cisco CME system, although individual IP phones can be exempted from all call blocking.

Individual phone users can be allowed to override call blocking associated with designated time periods by entering **personal identification numbers (PINs)** that have been assigned to their phones.

For IP phones that support soft keys, such as the Cisco IP Phone 7940G and the Cisco IP Phone 7960G, the call-blocking override feature allows individual phone users to override the call blocking that has been defined for designated time periods. The system administrator must first assign a personal identification number (PIN) to any phone that will be allowed to override call blocking.

Then, to override call blocking, the phone user presses the Login soft key on the phone and enters the PIN that is associated with the phone. Note that logging in to a phone with a PIN only allows the user to override call blocking that is associated with particular time periods. Blocking patterns that are created with the 7-24 keyword in the after-hours block pattern command are in effect 7 days a week, 24 hours a day, and they cannot be overridden by using a PIN.

When PINs are configured for call-blocking override, they are cleared at a specific time of day or after phones have been idle for a specific amount of time. The time of day and amount of time can be set by the system administrator.

From this good CME doc;

http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/admin/configuration/guide/cmeblock.html

There is also this 3rd party product;

http://www.andtek.com/communications-products-lockout.html

Hope this helps!

Rob