Need to use ethtool instead of mii-tool to do this.  My comment:

  #
  # Linux is apparently changing from mii-tool to ethtool but some drivers
  # don't support the new interface (3c59x), some don't support the old
  # interface (e1000), and some (eepro100) support the new interface just
  # enough that they can report success but not actually do anything.  Sweet!
  #

This requires that we load ethfind on the nodes, though the script will
continue to work if it isn't (though will not work for e1000 cards).