exception sometimes when clicking on tables in the Properties UI such as bundles

java.lang.ClassCastException: org.eclipse.jface.viewers.TreeViewer cannot be cast to org.eclipse.ui.part.PageBookView$SelectionProvider
	at org.eclipse.ui.part.PageBookView.postSelectionChanged(PageBookView.java:907)
	at org.eclipse.ui.part.PageBookView.access$3(PageBookView.java:905)
	at org.eclipse.ui.part.PageBookView$3.selectionChanged(PageBookView.java:172)
	at org.eclipse.jface.viewers.StructuredViewer$3.run(StructuredViewer.java:888)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
	at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
	at org.eclipse.jface.viewers.StructuredViewer.firePostSelectionChanged(StructuredViewer.java:886)
	at org.eclipse.jface.viewers.StructuredViewer.handlePostSelect(StructuredViewer.java:1226)
	at org.eclipse.jface.viewers.StructuredViewer$5.widgetSelected(StructuredViewer.java:1251)
	at org.eclipse.jface.util.OpenStrategy.firePostSelectionEvent(OpenStrategy.java:262)
	at org.eclipse.jface.util.OpenStrategy.access$5(OpenStrategy.java:256)
	at org.eclipse.jface.util.OpenStrategy$3.run(OpenStrategy.java:433)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)