route {
        force_rport();

...Irrelevant part...
		
		t_check_trans();

        if (loose_route()) {
                xlog("L_ERR", "Attempt to route with preloaded Route's [$fu/$tu/$ru/$ci]");

                if (!is_method("ACK"))
                        sl_send_reply("403","Preload Route denied");

                exit;
        }

...Irrelevant part...

        if ($rU==NULL) {
                sl_send_reply("484","Address Incomplete");
                exit;
        }
		
        #FreeSWITCH
        route(freeswitch);

        #Outbound
        route(outbound);

        if (!lookup("location", "m")) {
                t_newtran();
                t_reply("404", "Not Found");
                exit;
        }

        setflag(ACC_MISSED);
        xlog("Reaching lowest Call Relay.\n");
        route(relay);
}

route[outbound] {
        xlog("Jumped to Outbound.\n");
        if(!is_method("INVITE")){
                return;
        }
        if ($rU=~"^[1-9][0-9]+$") {
                xlog("FS tries to call PBX! $rU@$rd:$rp via $si");
                $rd="192.168.1.30";
                $rp="5060";
                force_send_socket(udp:192.168.1.150:5060);
                route(relay);
                exit;
        }
}

route[freeswitch] {
        if(!is_method("INVITE")){
                return;
        }
        if ( ($rU=~"^[5]$" || $rU=~"^[7]$") && src_ip==192.168.1.30 && src_port==5060) {
                xlog("PBX tries to call FS! $rU@$rd:$rp via $si");
                $rd="10.250.5.50";
                $rp="5090";
                force_send_socket(udp:10.250.5.3:5080);
                route(relay);
                exit;
        }
}

route[relay] {                  

        if (is_method("INVITE")) {             

                if (has_body("application/sdp") && $si=="192.168.1.30") {
                        xlog("Offer rtpp Inbound.\n");
                        rtpproxy_offer("rei");
                }else{
                        xlog("Offer rtpp Outbound.\n");
                        rtpproxy_offer("rie");
                }
                t_on_branch("per_branch_ops");
                t_on_reply("handle_nat");
                t_on_failure("missed_call");
        }

        if (is_method("CANCEL|BYE")) {
                rtpproxy_unforce();
        }

        if (!t_relay()) {
                send_reply("500","Internal Error");
        };
        exit;
}

branch_route[per_branch_ops] {
        xlog("new branch at $ru\n");
}

onreply_route[handle_nat] {

        if( is_method("ACK") && has_body("application/sdp")){
                xlog("Answer rtpp reply\n");
                rtpproxy_answer("rie");
        } else if(has_body("application/sdp")) {
                xlog("Offer rtpp reply\n");
                rtpproxy_offer("rei");
        }
        xlog("incoming reply\n");
}

...Irrelevant part...