OBi200:
Physical Interfaces -> Phone1 Port->
CallWaitingEnable: unchecked
ForwardOnBusy: checked
ForwardOnBusyNumber: pp(200222222)
OBi100:
Voice Services -> OBiTalk Service -> InboundCallRoute: ph
Replace 200222222 with the OBi number of the destination OBi100
Use OBi Expert to make the above changes
The OBi200 must be on an active call, you can't just take it off-hook to test
