Finally answering the call first made in 2003 and ultimately "deferred to a future release," Sun Microsystems is giving users a 64-bit plugin integrated into Java 6 Update 12. The new update also includes a 64-bit version of Webstart, a framework which offers end-users the ability to start Java applications over a network or the internet.
The 64-bit plugin is required for 64-bit browsers and comes included as part of the Java Runtime Environment. Users planning to run 32-bit and 64-bit browser interchangeably must install both 32-bit and 64-bit versions of the JRE.
In addition to the 64-bit plugin, Java 6 Update 12 offers official Windows 2008 support, better performance, and no less than 140 bug fixes.