Problem went away after that day. By mid-April I'm going to forward my GV lines to CallCentric, since I have an old dormant account there, and get free incoming calls to the OBi. Since that's not using XMPP, I'm hoping it will work fine.
On outgoing calls I haven't decided if I'm going to a) dial them all on my cell or use my PC to call via GV by ringing the house phone b) getting a XTTN Bluetooth device so that the house phone calls out on the cell line or c) paying for outbound service.
I don't make a lot of outbound calls, and when I do I'm usually at my desk so GV calling my house or cell phone should still work fine.