Lucid upstart job that will emit fake event ...

network-interface-loopback.conf

description "Configure loopback network interface"

start on net-device-added INTERFACE=lo
stop  on net-device-removed INTERFACE=lo

pre-start script
    [ -d /var/run/network ] || /bin/mkdir -p /var/run/network

    /sbin/ifconfig lo 127.0.0.1 up

    /sbin/initctl emit -n net-device-up IFACE=lo LOGICAL=lo ADDRFAM=inet METHOD=loopback --no-wait
end script

post-stop script
        /sbin/initctl emit -n net-device-down IFACE=lo LOGICAL=lo ADDRFAM=inet METHOD=loopback --no-wait

        [ -d /var/run/network ] || /bin/rm -rf /var/run/network/*
end script