In message <20040419181559.GF14175@sanctum.takilma.net>Ben Collver writes
>I don't know if 3c509's are affected, but I had some 10/100 3c595's that
>simply would not work at 100mbit unless they were connected together with a
>crossover cable.  They won't work at 100mbit with my switch.  It doesn't
>matter if its NetBSD, Linux, or Windows.  They worked perfectly at 10mbit
>though.

If memory serves, the 3c595 didn't do NWAY, which may explain
your problem.