Unhandled event loop exception

org.eclipse.swt.SWTException: Failed to execute runnable (java.lang.ClassCastException: org.jboss.tools.seam.ui.pages.editor.figures.DiagramFigure)
	at org.eclipse.swt.SWT.error(SWT.java:3777)
	at org.eclipse.swt.SWT.error(SWT.java:3695)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:136)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3800)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3425)
	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2384)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2348)
	at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2200)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:495)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:490)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:386)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1236)
Caused by: java.lang.ClassCastException: org.jboss.tools.seam.ui.pages.editor.figures.DiagramFigure
	at org.jboss.tools.seam.ui.pages.editor.PagesEditor$ModelSelectionProvider.setSelectedModelObject(PagesEditor.java:630)
	at org.jboss.tools.common.editor.AbstractSelectionProvider.setSelection(AbstractSelectionProvider.java:38)
	at org.jboss.tools.common.model.ui.select.XModelObjectSelectionProvider.setSelection(XModelObjectSelectionProvider.java:86)
	at org.jboss.tools.common.model.ui.select.SelectObjectWizard$1.run(SelectObjectWizard.java:58)
	at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:178)
	at org.eclipse.ui.internal.UISynchronizer.syncExec(UISynchronizer.java:150)
	at org.eclipse.swt.widgets.Display.syncExec(Display.java:4251)
	at org.jboss.tools.common.model.ui.select.SelectObjectWizard.execute(SelectObjectWizard.java:49)
	at org.jboss.tools.common.model.util.FindObjectHelper.findModelObject(FindObjectHelper.java:40)
	at org.jboss.tools.common.model.files.handlers.CreateFileSupport$1.run(CreateFileSupport.java:206)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:133)
	... 22 more