by no means am i an expert but i had problems with jdk1.5.0 for windows installation. i downloaded the latest 1.4.0 version and it worked perfectly. i am guessing that the download they have on the java.sun.com site is not correct or missing some code. if you can use a later version, please try that. if not, then you will need one of the more experienced people to help with your problem.
Time is mother nature's way of keeping everything from happening at once. And this is a tiny ad: