Pins 2 and 3 on the DB9 need to cross over. I am sure you could use a null modem adapter, but you only need pins 2,3,4 and 5. I build my own cables with DB9 to RJ45 hoods and a CAT5 patch cable.

By the way the method outlined above will not give you any message count on the display and the phone will have to have a MWXXX button and a VMMSG button if that extension wants to have it's own voicemail.

There are other ways to do it.............

Todd Tarkington
Communication Experts Group, Inc.
(972)444-8202