ruby script for wakeonlan not working in 10.6

I have a WakeOnLan ruby script that I execute on my MacBook Pro in order to turn on a specific Ubuntu Linux machine on my LAN. This script worked under OS X 10.5, but no longer works on 10.6. Any ideas?

Code:

#!/usr/bin/env ruby

require 'socket'
include Socket::Constants

mac = 'XX:XX:XX:XX:XX:XX'   #correct mac omitted for posting
ip = '255.255.255.255'

@magic ||= ("\xff" * 6)
mac_addr = mac.split(/:/).collect {|x| x.hex}.pack('CCCCCC')
@magic[6..-1] = (mac_addr * 16)
@ip_addr = ip
sock = UDPSocket.new
sock.setsockopt( SOL_SOCKET, SO_BROADCAST, 1 )
sock.connect( @ip_addr, Socket.getservbyname( 'discard', 'udp' ) )
sock.send( @magic, 0 )