Java 1.4, 1.5 and Mustang-ea and Linux applets
jdk6-ea does not work for up applets in linux still.
Going to firefox faq page, in order to have applets work, one must also "ln -s" file found in jdk6/jre/plugin/i386/ns7/l*.so to firfox plugin folder, commonly in linux in /usr/lib/firefoxxx/plugins, and then give it permissions.
Compare getting Flash runtime plugin instructions to java plug in instructions from Firefox FAQ.
it be nice if the installer would fix so that applets and webstart work in linux.