Seems like CLASSPATH=/opt/sun-jdk-1.4.0/lib/rt.jar doesn't exist -- it's in /opt/sun-jdk-1.4.0/jre/lib/rt.jar. I'm not sure if this is at the root of my problem, but after a fresh emerge of *any* jdk, setting the system vm with java-config and then updating the environment, any .class file run through the "java" program returns a NoClassDef error.
changed files/sun-jdk-1.4.0