I looked at the instructions that you gave, benji, and I got to looking at what was in my mozilla plugins directory. The java plugin is in there...well a link to it is and that is what the instructions were trying to get me to do. But the plugin still does not show up in the plugins list and doesn't work. Java is installed and everything seems to be in its place. I'm thinking that maybe some other setting is keeping it from working. I tried pasting the actual plugin file in there but that didn't help. I also tried one of the other plugins that was in the java/j2re1.4.2_03/plugin/i386 directory. Those didn't help either. One of them cause mozilla to not start up...but that wasn't very useful.
And thanks for the welcome!