you should be able to play burnout 3 online, the only problem i can see is if you need to use your cs login to play
have you been able to register your username with cs? you should have done this when you first got the network adapter, if not try deleting your network config from the memory card then make a new one and see if you can connect, if that doesn\'t work then you need to contact sony, there should be a number in the book that came with your network access disc and ask them for a new network access disc