Kubuntu Hardy
How I made Host networking work with Virtualbox and bridging.
My /etc/network/interfaces
auto lo
iface lo inet loopback
address 127.0.0.1
netmask 255.0.0.0
auto eth0
iface eth0 inet manual
up ifconfig $IFACE 0.0.0.0 promisc
down ifconfig $IFACE down
auto tap0
iface tap0 inet manual
up ifconfig $IFACE 0.0.0.0 up
down ifconfig $IFACE down
tunctl_user snisd
auto br0
iface br0 inet dhcp
bridge_ports eth0 tap0
bridge_stp off
bridge_maxwait 5