It seems like we have some incompatibilities with the OpenJDK implementation of Java, both in DrJava as well as in ConcJUnit. I don’t have the exact details on the DrJava problem, but Corky mentioned that there were display problems.
For ConcJUnit, it seems like the instrumented rt.jar file that I create somehow is invalid and the JVM cannot be initialized:
Error occurred during initialization of VM java/lang/ClassNotFoundException: error in opening JAR file /home/mgricken/drjava/drjava-concjunit/rt.concjunit.jar