In src/share/java/runtime/classloader.c, the function createInternalClass()
goes to some effort to return a string describing the reason it has failed
to load a class. This string is completely ignored by both functions which
call createInternalClass (LoadClassFromFile and LoadClassFromZip).

This extra information would be particularly helpful when trying to track
down the cause of "Failed to load java.lang.System" problems during
startup.