A number of security issues are addressed in the update. The release supports all Intel and PowerPC-based Macs, while Java SE 6 is available on 64-bit, Intel-based Macs only. Java for Mac OS X 10.x Update 2 delivers improved reliability and compatibility for several editions of Java 1.4.2 on Mac OS X. Apple has released Java updates for Mac OS X 10.4 and 10.5 ( Tiger and Leopard) users.