I would think that I should be able to ping from the mac to a vista laptop with a known good crossover cable but this is not happening.
I tested the cable going from my laptop to another old xp and it pings fine so cable is good.
I do see a green link light with activity on the laptop when I connect the laptop to the mac using crossover cable but still no successful pings. I can now ping the internal mac nic by doing a ping 126.96.36.199 with Mac TCping so mac nic appears to be good.
I now see a port address below the IP address in the Mac. It is listed as Hardware address: 00 05 02 57 9A E9 TCP/IP is version 1.3
Does this add anything relevant?