[OpenSER-Users] NAT configuration example

Hello, can somebody send me an functional openser.cfg with NAT support? I am unable to find and working example on the web. May be it will be good to add one to openser web or voip-info.org. I have this situation: NATed clients | NAT router | OpenSER | internet (or another clients, alternative provider, ...) OpenSER has an real IP (not private), but NAT clients have internet IP, masqueraded to another real IP. Is it possible to make a configuration which can use nathelper to fix these packets? For example an asterisk client on internet is still sending RTP packets to my openser and it is not accepting them (what is right). Do I require "rtpproxy" on my OpenSER? I do not want RTP traffic on my openser router, only SIP and client-to-client RTP stream, if it is possible. How to make it working without sip connection tracking on NAT routers? Is it possible? Can anybody tell me more how RTP NAT masquerade is working without SIP connection tracking support? Thank you. SAL