When running an install of 6.0, at the LILO options screen, adding the option 'append="ether=0,0,eth1"' to enable detection of a second ethernet card causes the LILO installation to fail. Going back and retrying without any options then succeeds. Then I must manually edit the lilo.conf file and rerun lilo after booting the new system.
This is fixed in later cuts of the installer (RawHide and 6.1)