I am having a problem getting both of my macs to see each other. I have a macbook and a G4 Mini, both connected to a linksys router over wireless. I can't seem to get them to communicate in order to share files. Internet works fine on both. Now if I connect the macbook to the router with a cable, file sharing magically works. Haven't tried connecting the mini with a cable, so I don't know if that has any effect. Do I need to open some ports on the router?