2 ext on one phone

[gleduc]

Hi,
I have a customer who want's 2 ext on the boss phone.

the first extention will ring only on the secretary phone (she need to have her extention too)
the second extention will ring only on the boss phone (no body have to know this extention execpt for the secratary)

When the boss call someone inside the company, we want other user see the second extention number on the display.

Is it a way to block outgoing number inside the same IPOffice?

Thanks