Thanks - that cracked it. I didn't realise that 1.0.1 existed, so when I used that,
used a 192.168.1.xxx address, and connected to the Arduino by a flipped cable
and not through a hub, ping worked.
The distribution examples seem a bit flakey - from your sketch, none of their
initialisation code is needed, and in fact hangs the sketch. I don't think turning
off the SD port is needed, either - the sketch works ok without it; since I want to
use both Ethernet and SD, I'll have to dig further.
I'm running the board through a USB=>Serial converter, so the Serial.print stuff
is fine.
Thanks again - after three or four days I was starting to suspect I'd got a dead
board, but with ping working I know the hardware itself is good, which is a relief.
Will