Activating built-in Ethernet on my Blue & White running YDL 4.0.1

[icl051]

Hi,

I've seen this discussed in the list archives but didn't really find  
a solution to the issue.

I've installed YDL 4.0.1 on a Blue & White 350MHz and am using the  
built-in Ethernet. Ethernet works fine when booted in to OS 9 or OS X  
but not in Linux.

ifup eth0 says that the device does not seem to be present.

Network Configuration gives conflicting information. I the hardware  
tab, it says that eth0 is ok and is described as GMAC (Sun GEM). If I  
go to the Devices tab though and try to activate the static IP  
configuration I've created, it says that eth0 does not seem to be  
present (just like ifup reports).

I'm experience with OS X but very new to Linux. Could anyone suggest  
an idiot's way to get ethernet working on my machine please?