Firefox questions

Hi gang. Not sure if this has been answered already, if so I couldn't find the answer. I upgraded myself to 1.5 downloading the tar ball from mozilla.org and extracting it into my home dir and been using it that way. Extensions work, etc... except for sime silly reason, java does not. It acts like java is not installed, yet I know it is. I guess it can't find the plugin, so anyone know how I teach it where the plugin is? or move it to the right place? -- David Crouch