‘Dropped’ internet service on XP home/pro machines but not Win2K

I use a Linksys WRT54G wireless router connected to Desktop computer(XP Home). MY ISP is Surewest broadband and provides eithernet gateway(no modem).

Two laptops XP Pro(use a Linksys USB wireless adapter) and Win2K(use Linksys PCMCIA wireless card) access the internet via the router. For the past 5 months, if either ‘XP’ machine is on but idle, I cannot access intrnet without log off/on or restarting. This never occurs with Win2K machine.

Last night I upgraded the Routers firmware and this was to fix the issue. Issue still present. Has anyone had this issue, if so how resolved?

Going Nuts