New install NIC problem

I installed k12ltsp(Red Hat) today and since it's ltsp it set my nic
"VT3043(Rhine)" to the local network.
I've been using that nic for my cable modem connection. Since I have a dual
boot system now, I installed a second nic "DECchip 21041(Tulip Pass 3)" to
now use for my internet connection for each OS.
XP took it just fine, but RH was a different story.
Upon booting it found the new hw and I right away checked the uhhh, you
know, the auto thing since my isp provides ip's dynamically.
Further into the boot it brought up the eth0 ok, but FAILED on eth1.
How do I fix that?