During the summer, ben11, a member from rpc1.org forum released a procedure to update the notoriously impossible to patch Matsushita UJ-857. You can now turn it into a region free drive! The entire discussion is worth reading for avoiding messing up your drive (found in MacBook Pro).
Firmwares for UJ-857 were compiled by the French website Powerbook-fr.com (in French but easily understandable.
[translation by Linathael]