Can you back-up a HD-DVD/Blu-ray combo DVD disc?

There is blu-ray or hd-dvd titles with a regular DVD layer, so you can play them on your regular DVD player. I wonder if you can back-up them.

If your computer drive is able to read these discs, you can make a backup of the DVD layer. For what I know, until now there is no way to make a copy of the blu-ray or the hd-dvd layers :wink: