debian64:~# dhclient
Internet Systems Consortium DHCP Client V3.0.4
Copyright 2004-2006 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

socket: Address family not supported by protocol - make sure
CONFIG_PACKET (Packet socket) and CONFIG_FILTER
(Socket Filtering) are enabled in your kernel
configuration!