As part of routine maintenance, you should be updating Java and a slew of other common browser plugins. If you haven’t been, don’t worry. Now is the perfect time to make sure you’re running the latest version of Java. Just head over to this Java webpage to ensure that you’re running the latest version which is (as of publishing) Version 6, Update 17. If you’re running an older version, head over to Java.com to download and then install the latest version for your operating system.
Why is now the perfect time to update your Java installation?
Holy Subject Change, Batman! What does Firefox have to do with updating Java?
If you hope to continue using Firefox to experience the “Java Powered Internet” and want to update to Firefox 3.6, then you’ll need to update your Java as well.
The technical reasons from an informative Java page:
Starting in Firefox 3.6, Mozilla foundation will drop support on OJI (Open Java Virtual Machine Integration) and will only support the standard NPAPI and NPRuntime interfaces. The Java Plug-in which is in Java version 6 update 10 or newer versions supports the NPAPI and NPRuntime interfaces. Therefore, starting with Firefox 3.6, Java-based applets will NOT work unless you are running Java version 6 Update 10 or newer.
So, go update Java if you’re browsing with an older version.