Here's What JDK 6 in Mac OS X Gets You:

Finally, Apple has shipped JDK 6 for Mac OS X 10.5. It's only for Intel Macs that can run 64-bit code, like Core 2 Duos and Xeons. If you have an early Intel Mac, you're probably out of luck.

You can run pure Java programs in 64-bit mode.

But a lot of popular programs, like those based on the Eclipse Rich Client Platform, cannot run in the new JDK. That includes Eclipse and Azureus.

However, you can use Eclipse as a development environment for JDK 6-based programs. Eclipse will detect the JDK 6 runtime, and you can use it in a Java project. If you run a little program like this:

public class Main {
public static void main(String[] args) {
 System.out.print("os.arch: ");
 System.out.println(System.getProperty("os.arch"));
}
}

It will print out:

os.arch: x86_64

instead of

os.arch: i386

as it would with the default Mac OS X JVM (1.5, 32 bit).

Whoopee !