We have a requirnment from the customer that he should reach a perticular pstn number if the ip phone does pick up after some time.I configured the cfna on a ccme router to a pstn for a phone but after some rings it gives me a fast busy signal.The same when configured for call forward all it works fine.We have integrated with unity express and when the unity pilot number is put in cfna the call is forwarded to unity.Is there something which has to be done on ccme for cfna to a pstn number?
