I have 2 computers. A desktop running Fedora Core 5 and a laptop running Windows Xp home.

In my router I have port forwarding set for tcp and udp ports 49154-49157 to the correct ip address.
This setup works fine for my laptop when i have the wired lan plugged in. The nat and dht as both green and working (in azureus)
However when I remove the same cable from my laptop and plug it into my desktop Azureus has a NAT problem. Ive disabled both SElinux and the firewall in my computer. Does anyone have any ideas on how to fix the NAT problem?

By default, Azureus checks for NAT issues on TCP port 28999 and if thats not open then you'll get reports of NAT blockage. If you open Azureus and try a NAT test again but change the port tested to one that you have opened in the range you listed above you shouldn't have a problem. You can also change your TCP/UDP listening port in the Configuration options to a nondefault port.

You can also find a wiki about this very issue: http://azureus.aelitis.com/wiki/index.php/NAT_problem