4.0.1 install on iMac 266 failing to recognize on-board ethernet

[Ken Simpson]

I'm trying to install 4.0.1 on my iMac but am running into an issue.
The installer doesn't seem to recognize the on-board ethernet. The
only network device I end
up with is the loopback device. I've tried both install and
install-text with the
same results. Is there an option I need to pass to the installer to load an 
appropriate module?

OS X works fine so it wouldn't appear to be a hardware issue.

TIA

Ken