Are you having trouble getting java to work with your firefox browser on Linux.
Unlike windows, where you install Java and lo it's setup with all the browsers seamlessly, on linux it appears to be different. It still requires some manual intervention to get this working.
We were trying to test an file upload applet for one of the products under test. The tests ran fine on Windows. But on Linux, despite reinstalling java and firefox, we couldn't get the applet to run.