Look at the top left hand corner of the graphic. What do you see? Would that be an ‘A’ in a hexagon? That’s a region code marking for Blu-ray discs.
Look at the two primarily red boxes on that graphic. What do you see? They are the Australian Film Classification ratings.
Australia is Region B for Blu-ray. The Region A marking on the back of the box is for North America.
This graphic is a scan of a portion of the back of the Australian Blu-ray release of No Country for Old Men. As it happens, the Australian release is region free. If you are wandering through an Australian shop that sells Blu-ray discs and stumble across this one, do yourself a favour. Ignore the Region A marking, and buy it. It will work and it will be worth it.
UPDATE (Friday, 15 August 2008, 1:35 pm): For some unknown reason I had the title of the movie in the heading to this post, and only there, as Old Country for Old Men. Now corrected.