[Dltk-dev] Unusual problem with PresentationReconciler; help please

[Gerald Rosenberg <gerald@xxxxxxxxxx>]

New user, generally following the Python and Lua code bases as 
examples.  Eclipse 3.3 and DLTK 0.9.1 sdk.

Running into this error, which does not *seem* to intersect my code 
-- the editor fails to open, giving the message "Error opening the 
editor".  Any advice or even guesses as to the source of the problem 
would be appreciated.

java.lang.ClassCastException: 
org.eclipse.jface.text.presentation.PresentationReconciler
	at 
org.eclipse.dltk.internal.ui.editor.SemanticHighlightingManager.install(SemanticHighlightingManager.java:288)
	at 
org.eclipse.dltk.internal.ui.editor.ScriptEditor.installSemanticHighlighting(ScriptEditor.java:2925)
	at 
org.eclipse.dltk.internal.ui.editor.ScriptEditor.createPartControl(ScriptEditor.java:1845)
	at 
org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:661)
	at 
org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:426)
	at 
org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:592)
	at 
org.eclipse.ui.internal.EditorAreaHelper.setVisibleEditor(EditorAreaHelper.java:263)
	at 
org.eclipse.ui.internal.EditorManager.setVisibleEditor(EditorManager.java:1405)
	at 
org.eclipse.ui.internal.EditorManager$5.runWithException(EditorManager.java:939)
	at 
org.eclipse.ui.internal.StartupThreading$StartupRunnable.run(StartupThreading.java:31)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at 
org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:123)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3659)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3296)
	at 
org.eclipse.ui.application.WorkbenchAdvisor.openWindows(WorkbenchAdvisor.java:801)
	at org.eclipse.ui.internal.Workbench$25.runWithException(Workbench.java:1342)
	at 
org.eclipse.ui.internal.StartupThreading$StartupRunnable.run(StartupThreading.java:31)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at 
org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:123)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3659)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3296)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2309)
	at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2219)
	at org.eclipse.ui.internal.Workbench$4.run(Workbench.java:466)
	at 
org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:289)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:461)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
	at 
org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:106)
	at 
org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:169)
	at 
org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:106)
	at 
org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:76)
	at 
org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:363)
	at 
org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:176)
	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:508)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:447)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1173)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1148)