Networking problems

I have 3 computers 1 wired to the wireless router and two wireless machines. All running Windows XP home SP2. On the wired machine I can access the shared documents of the other computers. However the wireless machines can not access the wired computer at all. I also cannot ping the wired machine from either wireless machines. All the machines access the internet through a wireless hub successfully. Another piece of the puzzle. All the machines are using Mcafee SecurityCenter. In the network view look I can see the wired machine from my wireless computers and an ip address is also shown. Any thoughts?