Only by software that gets around RPC2, like this
Works with all DVD-drives, no matter what region code it has
DVD43-free ... www.dvd43.com might work. but it's a little hit or miss in some cases
http://www.dvdidle.com/dvd43.htm - and a non-free source-fork of DVD43
Of course, these may not work 100% with all drives in ALL systems, but they generally remove the necessity to RPC-1 hack a drive, which still needs software intervention to prevent software region control taking over, often with fewer than maximum changes.