One thing worth trying might be a test over loopback - especially if
there is a way to increase the loopback MTU to the size of your
interface card.
In the test below, the sender is a Pentium Linux box and the
receiver is an UltraSparc.
Are you sure it isn't the UltraSparc?-) I guess it isn't, otherwise
there would be a large number of sends, but small number of
receives...
Also, what happens if you try a message size of 4097 bytes?
rick jones