Hello, am writing the same problem 2nd time at list, didn't get any reply from anybody yet! Anbody could plz mind replying ;) I have been able to compile the kernel 2.6.18 with h323 support and iptables version 1.3.5, however, I am still not able to conduct (h323) calls between the outside and NAT endpoint. First, after rebuild of kernel and reboot, i have loaded ip_nat_h323 and ip_nat_h343 module. When placing a call from the NAT endpoint to a remote endpoint. The same symptoms occur as before I applied the patch/module. The remote user is unable to hear (recieve voice) from the inside NAT endpoint. The remote use can accept the call and recieve everything fine. Do you have any answer to this riddle. I hope it is simple and that I am missing a "step" somewhere, or there is something wrong with the connection tracking, which is not replacing/writing the header when send information to the NATed endpoint, below is the detail description of a call. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com