I've had zero luck with port forwarding 5900 to another Ubuntu machine. I'm running Ubuntu 8.10 64-bit server for my DHCP/NAT and hopefully someday VPN services. All in terms of internet access works great for connecting clients with the exception of the "Pinger Plus" device which cannot get an IP from my Ubuntu server, however, can obtain an address and ping with no problems if I use a windows or Cisco DHCP server. Not a huge deal but if anyone happens to know.

 As far as the port forwarding goes, I've tried every flavor of the instructions above. Help is greatly needed!

Thanks!