As far as legacy Mac operating systems go, OS X 10.3 is Panther (supports up to Java 4), OS X 10.4 is Tiger (supports up to Java 5), OS X 10.5 is Leopard (supports up to Java 5), OS X 10.6 is Snow Leopard (supports up to Java 6). The two vetoes to the update beyond Java 5 were jasonharper and I...