I had been unable to get the Java Runtime Environment working for my online classroom, which was serious because I'm in graduate school. In thread http://www.linuxquestions.org/questi...ething-757868/
, I received advice about the problems with Icedtea and about how to download Java from the Sun website.
The latest Java straight from the Sun site didn't work for me, but I just discovered that I didn't need it (or Icedtea, I guess) anyway. Java 6, downloadable from the Debian repositories using Synaptic, does the job. I saw it in the repositories, but apparently never downloaded all the exact items I needed.
To get Java with Synaptic, download three items (but select only two, because one is a dependency and will be downloaded automatically): sun-java6-jre (Synaptic will automatically download sun-java6-bin with this), and sun-java6-plugin.
As soon as Synaptic has downloaded and installed these, go to or reload the page that requires Java; it will now work correctly. Restarting your browser is not necessary.
Ha...after five weeks of awkward workarounds for my inability to use Java in Firefox, I win.