I have a customer who tried running the following:

    @Override public void attachTo( final CommandEnvironment env ) {
super.attachTo(env);
classLoader = env.getJavaFileManager().getClassLoader( CLASS_PATH );
    }

Jackpot currently returns an unmodified DefaultFileManager instance, which throws the following exception:

Caused by: java.lang.UnsupportedOperationException
at com.sun.tools.javac.util.ListBuffer.add(ListBuffer.java:205)
at
com.sun.tools.javac.util.DefaultFileManager.getClassLoader(DefaultFileManager.java:664)
at sixexperiment.PEC.attachTo(PEC.java:20)

This is due to ListBuffer.add() not being implemented.