There are no such things as "stupid" questions. However if you think your question is a bit stupid, then this is the right place for you to post it. Please stick to easy to-the-point questions that you feel people can answer fast. For long and complicated questions prefer the other forums within the support section. Before you post please read how to get help
Anyway, why does 64-bit use openjdk? I was having problems with it so I looked for sun-jdk and was surprised so see that it was there. So I installed it and it's working fine. Should it *not* be working fine?