Encoding of disks in the US and trying to watch them in Australia?

I am looking to buy the complete season 2 of army wives. The only place I can get it is on Amazon.com. It has a warning when I go to purchase it that it may be encoded so that only people in the US can watch it. I live in Australia. Can some one tell me if I will be able to watch it here or not if I buy it. I have a playstation 3 and an Australian DVD player. Are play stations encoded to only play games and movies from the country they were purchased. Please help. Any advice would be greatly appreciated.