Get the Java 1.5 from the developers site, then follow these steps (your are stepping into a program that is quite user ready yet). Install the package, then launch /Applications/Utilities/Java/J2SE\ 5.0/Java\ Preferences.app and inside that choose in the pull down J2SE 5.0 setting AND is the window below that in the "Java Applications Runtime Settings" drag the J2SE 5.0 top the top, then save. This will tell you computer to use 5.0 first, if can run the Java application.