[Serusers] RTPProxy h/w and s/w

Hello, I am newbie to this field. We are trying to use a separate card for handling the rtp voice traffic but use the RTPProxy (IPtel) software to handle the NAT issues. We have been fairly successful in doing that. The problem now is to handle asymmetric NATs. I hear one way audio.We are not sure how to handle this when there is one machine running rtpproxy software and another card with a different IP handling the SDP (In nathelper.c of Openser new_ip= card IP). In the symmetric NAT scenario this works fine. I would appreciate and pointers to modify rtpproxy for this configuration. We use rtpproxy 0.3, Opneser 1.1.0. -the card only handles RTP data and has its own GbE port - made changes to nathelper.c nathelper.cfg source code to account for separate IP addrs - made changes to RTPProxy to open channels for RTPtraffic flow on the card. -Openser,RTPProxy and the card , all 3 different Public IPs Thanks Nithin