Invalid thread access in CEP

org.eclipse.swt.SWTException: Invalid thread access
at org.eclipse.swt.SWT.error(SWT.java:3884)
at org.eclipse.swt.SWT.error(SWT.java:3799)
at org.eclipse.swt.SWT.error(SWT.java:3770)
at org.eclipse.swt.widgets.Widget.error(Widget.java:463)
at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:355)
at org.eclipse.swt.widgets.Tree.setRedraw(Tree.java:4715)
at org.eclipse.jface.viewers.AbstractTreeViewer.labelProviderChanged(AbstractTreeViewer.java:2116)
at org.eclipse.jface.viewers.ContentViewer.handleLabelProviderChanged(ContentViewer.java:193)
at org.eclipse.jface.viewers.StructuredViewer.handleLabelProviderChanged(StructuredViewer.java:1142)
at org.eclipse.jdt.internal.ui.javaeditor.JavaOutlinePage$JavaOutlineViewer.handleLabelProviderChanged(JavaOutlinePage.java:426)
at org.eclipse.jface.viewers.ContentViewer$1.labelProviderChanged(ContentViewer.java:97)
at org.eclipse.jface.viewers.BaseLabelProvider$1.run(BaseLabelProvider.java:74)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.runtime.Platform.run(Platform.java:888)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:48)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
at org.eclipse.jface.viewers.BaseLabelProvider.fireLabelProviderChanged(BaseLabelProvider.java:72)
at org.eclipse.jface.viewers.DecoratingStyledCellLabelProvider$1.labelProviderChanged(DecoratingStyledCellLabelProvider.java:77)
at org.eclipse.ui.internal.decorators.DecoratorManager$2.run(DecoratorManager.java:448)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.ui.internal.decorators.DecoratorManager.fireListeners(DecoratorManager.java:446)
at org.eclipse.ui.internal.decorators.DecoratorManager.update(DecoratorManager.java:1101)
at com.cenqua.clover.eclipse.exclusion.ExclusionLabelDecorator.decorationChanged(ExclusionLabelDecorator.java:64)
at com.cenqua.clover.eclipse.exclusion.DecorationPreferenceChangeListener.preferenceChange(DecorationPreferenceChangeListener.java:16)
at org.eclipse.core.internal.preferences.EclipsePreferences$2.run(EclipsePreferences.java:753)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.preferences.EclipsePreferences.firePreferenceEvent(EclipsePreferences.java:756)
at org.eclipse.core.internal.preferences.EclipsePreferences.put(EclipsePreferences.java:769)
at org.eclipse.core.internal.preferences.PreferencesService$1.visit(PreferencesService.java:174)
at org.eclipse.core.internal.preferences.EclipsePreferences.accept(EclipsePreferences.java:105)
at org.eclipse.core.internal.preferences.PreferencesService.applyPreferences(PreferencesService.java:195)
at org.eclipse.core.internal.resources.ProjectPreferences.read(ProjectPreferences.java:233)
at org.eclipse.core.internal.resources.ProjectPreferences.updatePreferences(ProjectPreferences.java:299)
at org.eclipse.core.internal.resources.File.updateMetadataFiles(File.java:405)
at org.eclipse.core.internal.localstore.RefreshLocalVisitor.visit(RefreshLocalVisitor.java:294)
at org.eclipse.core.internal.localstore.UnifiedTree.accept(UnifiedTree.java:106)
at org.eclipse.core.internal.localstore.FileSystemResourceManager.refreshResource(FileSystemResourceManager.java:784)
at org.eclipse.core.internal.localstore.FileSystemResourceManager.refresh(FileSystemResourceManager.java:768)
at org.eclipse.core.internal.resources.Resource.refreshLocal(Resource.java:1528)
at org.eclipse.core.internal.refresh.RefreshJob.runInWorkspace(RefreshJob.java:166)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)