diference between jdk 1.6 and 1.5

hai ranches,

i am preparing for scjp 1.5 exam but currently using java vereion 1.6 for my codimg practices.
so i want to know is it suitable thing to do?

the reason for using version 6 is
when i try to install netbeans 6.0, it is ask for install jdk 5 or 6 versions
but already i have installed jdk 1.5 update 6 in my machine
what is this problem?
so decided to install version 6

so now i want to know is it a good idea to use jdk 6
because i am preparing for scjp 1.5 exam

well you can use jdk 1.6 for preparing 1.5. 1.6 will provide backward compatibility. I have only came across one difference and it is related to the number of errors generated by these two versions in a specific program. But that's irrelevant I think....

It shouldn't be a problem, however I'm curious why I see so many people going for the scjp5 when version 6 is now out and there is not that much difference?