I have line1 registered with whistlephone.com at SPA9000, and registered PAP2T with the SPA9000. Outgoing calls are good from the PAP2T as an extension of the SPA9000.
Incoming call is through AA at the SPA9000, music played and prompt for extention #, I then enter extension # (in my case 201), the extenstion rings at the PAP2T. But as soon as I pick up the handset at the PAP2T, the call drops.
The same PAP2T can make outgoing and incoming calls when directly configured to whistlephone.com