Error using tool box

When i try to run genetic algorithm in toolbox then iteration starts but after a time following error in red fonts appears. please help.

if true
  % code
Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: com.mathworks.jmi.types.MLArrayRef cannot be cast to [D
  at com.mathworks.toolbox.optim.OptimGUIPanels$CompleteRun.matlabEvent(OptimGUIPanels.java:672)
  at com.mathworks.jmi.MatlabMCR$AWTReplyEvent.run(MatlabMCR.java:1637)
  at java.awt.event.InvocationEvent.dispatch(Unknown Source)
  at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
  at java.awt.EventQueue.access$200(Unknown Source)
  at java.awt.EventQueue$3.run(Unknown Source)
  at java.awt.EventQueue$3.run(Unknown Source)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
  at java.awt.EventQueue.dispatchEvent(Unknown Source)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
  at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
  at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
  at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
  at java.awt.EventDispatchThread.run(Unknown Source)
end