1  –  MASK hex-string

 Provides a mask for the called address extension facility. Using
 logical AND, the mask is merged with the called address extension in
 the incoming call and the result is compared with the extension value.

 By default no extension mask is used.

2  –  VALUE hex-string

 Provides a value for the called address extension facility. This value
 is compared with the address extension in the incoming call (after
 merging as described in EXTENSION MASK).

 By default no extension value is used.