Linksys Wireless Router Problems (Yes, I've searched the forums)

[Infestator]

I'm having difficulty getting people to connect to my SHOUTcast server, which I'm assuming is because of my router. It's a Linksys WRT54G wireless router. I've tried everything including:

1) Setting a static ip on this computer
2) Port forwarding 8000-8001 on both TCP and UDP for this computer
3) Disable Windows XP firewall
4) Tried my computers internal IP address to connect as well as the one given by the router on my computer
5) I've even tried setting this computer as a DMZ

The only problem I have is that when I disable the DHCP server for the router, my brother's internet, which is connected by wireless connection, no longer works, while mine (connected through ehternet) still does.

Any suggestions?