CompareDirectories exceptions

Error during dispatching of java.awt.event.InvocationEvent[INVOCATION_DEFAULT,runnable=javax.swing.SystemEventQueueUtilities$ComponentWorkRequest@57ae85,notifier=null,catchExceptions=false,when=1159791196341] on sun.awt.windows.WToolkit@b85c17
java.util.ConcurrentModificationException
at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:449)
at java.util.AbstractList$Itr.next(AbstractList.java:420)
at org.intellij.idea.dirdiff.model.FileTreeNode.hasFilteredChildren(FileTreeNode.java:432)
at org.intellij.idea.dirdiff.model.FileTreeModel.isLeaf(FileTreeModel.java:124)
at javax.swing.plaf.basic.BasicTreeUI.paint(BasicTreeUI.java:1155)
at javax.swing.plaf.metal.MetalTreeUI.paint(MetalTreeUI.java:152)
at javax.swing.plaf.ComponentUI.update(ComponentUI.java:142)
at javax.swing.JComponent.paintComponent(JComponent.java:742)
at javax.swing.JComponent.paint(JComponent.java:1005)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JViewport.paint(JViewport.java:728)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintWithOffscreenBuffer(JComponent.java:4963)
at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:4916)
at javax.swing.JComponent._paintImmediately(JComponent.java:4859)
at javax.swing.JComponent.paintImmediately(JComponent.java:4666)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:451)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:114)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:143)
at com.intellij.ide.IdeEventQueue.a(IdeEventQueue.java:128)
at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:26)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)