NodeTemplateProvider throws NPEs in load()

05.06.2009 17:22:53 ERROR [org.hippoecm.frontend.JcrObservationManager$JcrListener.process():667] Error occured when processing event
java.lang.NullPointerException
at org.hippoecm.frontend.editor.model.NodeTemplateProvider.load(NodeTemplateProvider.java:158)
at org.hippoecm.frontend.editor.model.AbstractProvider.size(AbstractProvider.java:75)
at org.hippoecm.frontend.editor.plugins.field.FieldPlugin$TemplateController.start(FieldPlugin.java:185)
at org.hippoecm.frontend.editor.plugins.field.FieldPlugin.updateProvider(FieldPlugin.java:118)
at org.hippoecm.frontend.editor.plugins.field.NodeFieldPlugin.onModelChanged(NodeFieldPlugin.java:91)
at org.apache.wicket.Component.modelChanged(Component.java:2105)
at org.hippoecm.frontend.editor.plugins.field.NodeFieldPlugin.onEvent(NodeFieldPlugin.java:123)
at org.hippoecm.frontend.model.event.ObservableRegistry$ObservationContext.notifyObservers(ObservableRegistry.java:76)
at org.hippoecm.frontend.model.event.JcrEventListener.onEvent(JcrEventListener.java:62)
at org.hippoecm.frontend.JcrObservationManager$JcrListener.process(JcrObservationManager.java:662)
at org.hippoecm.frontend.JcrObservationManager.processEvents(JcrObservationManager.java:832)
at org.hippoecm.frontend.Home.processEvents(Home.java:146)