you should be able to add a line to /etc/sysconfig/network-scripts/ifcfg-eth0 ETHTOOL_OPTS="speed 10 duplex half autoneg off" and the change will take place at boot up, or anytime you restart the interface.
That's _exactly_ the answer for which I was looking. Unfortunately, it begs a couple of other questions... 1) How did you know that? 2) How could I have known that? :-) 3) If I add my own text to ifcfg-eth0, will the network configuration GUI deal with it properly? --wpd