Issue with home network play?

[Sybell]

I got three computers finally hooked up at home where wanted to duplicate the multiplayer capability we have at teh office. I have the computers as part of a workgroup, all running XP Pro SP2 with firewalls off and no antivirus. I am using a Linksys wireless router WRT54GS that is hooked to my Cable Modem. It is functioning as a DHCP issuing IP addresses to my computers. I can login to Novaworld with accounts on computer a and b. I start hosing on computer a, can search and find the game that is hosted on computer a on computer b's dfx, and click join. However it gives me an error and says either the server cannot be reached or has a problem issuing join and to contact tech support. I found out through further troubleshooting that computer b is knocking computer a off of novaworld once it has tried to connect to join the game. I then cannot get back into novaworld on computer a until I restart. It is not affecting internet traffic at all. I can hit all sites in my browser but the game just cannot reach novaworld. What is going on here? Is novaworld cutting me off because it sees one IP address for two games or something? If anybody has any ideas I would really appreciate it. I was really looking forward to playing with the family on this.