Ubuntu VZ container and lo interface

If you look at VZ image of Ubuntu 11.04 , you'll see that udev is excluded from startup. It seems to be incorrect, because without udev "net-device-added INTERFACE=lo" event is not emitted and loopback interface remains unconfigured... At least, this behavior appeared after updating this image to 11.10. I don't remember if lo interface was present in original 11.04 image.