When I try open the page editor for an xhtml file I get this exception:

java.lang.NullPointerException
at org.jboss.tools.jst.jsp.jspeditor.JSPMultiPageEditor.createPagesForVPE(JSPMultiPageEditor.java:452)
at org.jboss.tools.jst.jsp.jspeditor.JSPMultiPageEditor.createPages(JSPMultiPageEditor.java:392)
at org.jboss.tools.jst.jsp.jspeditor.JSPMultiPageEditorPart.createPartControl(JSPMultiPageEditorPart.java:125)
at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:661)
at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:428)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:594)
at org.eclipse.ui.internal.PartPane.setVisible(PartPane.java:306)
at org.eclipse.ui.internal.presentations.PresentablePart.setVisible(PresentablePart.java:180)
at org.eclipse.ui.internal.presentations.util.PresentablePartFolder.select(PresentablePartFolder.java:270)
at org.eclipse.ui.internal.presentations.util.LeftToRightTabOrder.select(LeftToRightTabOrder.java:65)
at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation.selectPart(TabbedStackPresentation.java:473)
at org.eclipse.ui.internal.PartStack.refreshPresentationSelection(PartStack.java:1256)
at org.eclipse.ui.internal.PartStack.setSelection(PartStack.java:1209)
at org.eclipse.ui.internal.PartStack.showPart(PartStack.java:1608)
at org.eclipse.ui.internal.PartStack.add(PartStack.java:499)
at org.eclipse.ui.internal.EditorStack.add(EditorStack.java:103)
at org.eclipse.ui.internal.PartStack.add(PartStack.java:485)
at org.eclipse.ui.internal.EditorStack.add(EditorStack.java:112)
at org.eclipse.ui.internal.EditorSashContainer.addEditor(EditorSashContainer.java:63)
at org.eclipse.ui.internal.EditorAreaHelper.addToLayout(EditorAreaHelper.java:217)
at org.eclipse.ui.internal.EditorAreaHelper.addEditor(EditorAreaHelper.java:207)
at org.eclipse.ui.internal.EditorManager.createEditorTab(EditorManager.java:779)
at org.eclipse.ui.internal.EditorManager.openEditorFromDescriptor(EditorManager.java:678)
at org.eclipse.ui.internal.EditorManager.openEditor(EditorManager.java:639)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2817)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2729)
at org.eclipse.ui.internal.WorkbenchPage.access$11(WorkbenchPage.java:2721)
at org.eclipse.ui.internal.WorkbenchPage$10.run(WorkbenchPage.java:2673)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2668)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2652)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2635)
at org.jboss.tools.common.editor.OpenEditorWizard.execute(OpenEditorWizard.java:78)
at org.jboss.tools.common.model.handlers.OpenEditorHandler.executeHandler(OpenEditorHandler.java:31)
at org.jboss.tools.common.meta.action.impl.XActionImpl.executeHandler(XActionImpl.java:65)
at org.jboss.tools.common.model.ui.action.XModelObjectAction.actionPerformed(XModelObjectAction.java:89)
at org.jboss.tools.common.model.ui.action.XModelObjectActionInvoker.execute(XModelObjectActionInvoker.java:36)
at org.jboss.tools.common.meta.action.XActionInvoker.invoke(XActionInvoker.java:53)
at org.jboss.tools.common.meta.action.XActionInvoker.invoke(XActionInvoker.java:40)
at org.jboss.tools.common.model.ui.select.SelectObjectWizard.openEditor(SelectObjectWizard.java:136)
at org.jboss.tools.common.model.ui.select.SelectObjectWizard.execute(SelectObjectWizard.java:47)
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)
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:2382)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2346)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2198)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:493)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:488)
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:382)
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)