The ApplicationClassLoader is actually what the Sun docs refer to as the SystemClassLoader. The RVM class should be renamed to reflect this change. The ClassLoader should manage the java.class.path system property internally. So all the command line parameters that modify the classpath will route through the ApplicationClassLoader. Existing args such as -jar, -classpath and -Djava.class.path= will be easy to redirect to this classloader. Currently jikes does not handle the -javaagent command line parameter correctly. The jar should also be added to the system classloader AND appended to the java.class.path system property.