thread cpu time measurement is not supported (java application weka error message)

[Dino Vliet]

Folks,
when running an experiment in weka in freebsd ports I get this error:
thread cpu time measurement is not supported
In the console I see this:
ava.lang.UnsupportedOperationException: Thread CPU time measurement is not supported        sun.management.ThreadImpl.isThreadCpuTimeEnabled(ThreadImpl.java:80)        weka.experiment.ClassifierSplitEvaluator.getResult(ClassifierSplitEvaluator.java:685)        weka.experiment.CrossValidationResultProducer.doRun(CrossValidationResultProducer.java:367)        weka.experiment.AveragingResultProducer.doRun(AveragingResultProducer.java:296)        weka.experiment.Experiment.nextIteration(Experiment.java:539)        weka.gui.experiment.RunPanel$ExperimentRunner.run(RunPanel.java:181)
        at sun.management.ThreadImpl.isThreadCpuTimeEnabled(ThreadImpl.java:80)        at weka.experiment.ClassifierSplitEvaluator.getResult(ClassifierSplitEvaluator.java:685)        at weka.experiment.CrossValidationResultProducer.doRun(CrossValidationResultProducer.java:367)        at weka.experiment.AveragingResultProducer.doRun(AveragingResultProducer.java:296)        at weka.experiment.Experiment.nextIteration(Experiment.java:539)        at weka.gui.experiment.RunPanel$ExperimentRunner.run(RunPanel.java:181)Done...
My java environment is:
weka-3.6.3javavmwrapper-2.3.5jdk-1.6.0.3p4_15
What seems to be the problem here?