With a fresh installation of TarHeel Linux 5, Java and Firefox are installed. However, Java plugin is not configured in Firefox. Here is the way to enable java plugin for Firefox.

First, find out where is the Java plugin with this command.

rpm -ql jre | grep libnpjp2.so

If your machine is installed with JRE version 1.6.0_20, you should see the following.

/usr/java/jre1.6.0_20/lib/i386/libnpjp2.so

Then, go to the Firefox plugin directory and add a link.

cd /usr/lib/mozilla/plugins
ln -s /usr/java/jre1.6.0_20/lib/i386/libnpjp2.so .

You do not even need to restart Firefox, Java plugin should already be available. In the Firefox browser, point to the following page to check it out.

about:plugins