How do I clear all of the java applets that have been downloaded?

I migrated firefox and other applications to my new mac so that I would not to reenter all of my passwords saved by firefox. However, it appears that the java applets were also transfered and one of these applets does not work with the new intel mac. I was able to get the same applet to work in safari, and I was able to delete the applet from safari as well, but was unable to do so in firefox. So, how do I clear all of the previously downloaded applets, or even better, just the one I want to? Clearing all of the recent history didn't work. Here is the site: http://www.mdbg.net/chindict/chindict.php == This happened == A few times a week