Dear All, I use openser 1.0.1 and use rtp proxy for some cases other than nat option. At voice calls I do not have any problem. But When I try to send fax,it is unsuccesful. I investigated the logs and saw that, after the reinvites ( to take the session from g729 to G711u bypass mode ), the last OK message's SDP that is sending from openser to user agent is not correct.Etheral logs are attached. Is it a bug of rtpproxy ? Any suggestion. Best Regards, Hakan.