The test is in regressionTestsInWaiting/RedefinePrivateStatic.sh.

The test does a RedefineClasses adding a static private method to the class. It then does a 'where' command which causes this:
main[1] where
Internal exception:
com.sun.jdi.InternalException: Unexpected JDWP Error: 23
at com.sun.tools.jdi.JDWPException.toJDIException(JDWPException.java:65)
at com.sun.tools.jdi.ReferenceTypeImpl.methods(ReferenceTypeImpl.java:464)
at com.sun.tools.jdi.ReferenceTypeImpl.getMethodMirror(ReferenceTypeImpl.java:102)
at com.sun.tools.jdi.LocationImpl.method(LocationImpl.java:103)
at com.sun.tools.example.debug.tty.Commands.dumpFrame(Commands.java:917)
at com.sun.tools.example.debug.tty.Commands.dumpStack(Commands.java:906)
at com.sun.tools.example.debug.tty.Commands.commandWhere(Commands.java:955)
at com.sun.tools.example.debug.tty.TTY.executeCommand(TTY.java:452)
at com.sun.tools.example.debug.tty.TTY.<init>(TTY.java:736)
at com.sun.tools.example.debug.tty.TTY.main(TTY.java:1038)