Hello, I'm trying to get rDNS to work on my public IP for my SBS 2k3 domain. My ISP says they setup rDNS 2 days ago. In my firewall logs (Zywall 10W) I can see many request coming in from name servers on port 53 but my firewall is blocking them from coming in only. Does port 53 need to be opened to my SBS box for the rDNS to work correctly? I have tried opening it to my server and then when I do an rDNS lookup at dnsstuff.com I get a SERVER FAILED message when it gets to my IP.