I see this too with edgy and totem-gstreamer. Autoplay works, totem dvd:// from command line works too. Playing from the totem menu movie->play disc it fails.
-- Video DVDs detected as DVD-ROMs https://launchpad.net/bugs/41312 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
