[Serusers] NAThelper module

Hi, I have that to implement a solution VOIP in my company. I am testing SER/RTPProxy, more I do not obtain to place rtpproxy to function. Below it follows the error. What I must make? Thank You. The version that I am using is: SER 0.8.12-TCP_nonb (i386/linux) rtpproxy 20040107 My archive of log (var/log/message) returns the error: ++++++++++++++++++++ ERROR +++++++++++++++++++++++++++++ /var/log/message Feb 27 18:09:47 blacksip ser[3588 ]: ERROR: send_rtpp_command: can't read reply from the RTP proxy Feb 27 18:09:58 blacksip ser[3586 ]: ERROR: send_rtpp_command: can't read reply from the RTP proxy Feb 27 18:09:58 blacksip ser[3586 ]: ERROR: on_reply processing failed ++++++++++++++++++++ ERROR +++++++++++++++++++++++ João Carlos Moura NiNeTel Telecommunications +55 85 264-9039