Previewed at WWDC, launching in the fall.
Apple Adds Java SE 6 to Leopard
This Java for Mac OS X 10.5 Update 1 adds Java SE 6 version 1.6.0_05 to your Mac. This update does not replace the existing installation of J2SE 5.0 or change the default version of Java.
The update requires Mac OS X 10.5.2 or later, and a 64-bit Intel-based Mac. Apple had previously seeded a developer's preview of Java SE 6 for Leopard to ADC developers.
The lack of Java 6 support when Leopard was released had received much criticism.