I've a call manager 4.2(3). Last week, we have installed a gateway ASCOM for put phones DECT to telephony over IP. On the call manager, I configure a gateway H323.
Everything is ok but one thing. When an IPPhone connected to the call manager call a DECT, IPPhone Cisco don't have ringback. Yet, DECT ring and after, communication is OK.
In the other direction, it's ok.