[Freeswitch-users] Both Way early media

Hi With help of pre_answer application I can receive DTMF while playing an early media announce in most cases but if destinations was in a Access Gateway with H.248 protocol I can play early media but can not receive DTMF. This is because of H.248 nature in pre answer phase ? I know that if even there was no a=sendrecv in sdp it was implicitly there but is there a way to force this in 183 response ? Regards M.Shirazi