What causes this ???

2010-08-26 12:47:01,911 [9212250]  ERROR - llij.ide.plugins.PluginManager - IntelliJ IDEA (Maia) IU-95.495  Build #IU-95.495
2010-08-26 12:47:01,911 [9212250]  ERROR - llij.ide.plugins.PluginManager - JDK: 1.6.0_21
2010-08-26 12:47:01,911 [9212250]  ERROR - llij.ide.plugins.PluginManager - VM: Java HotSpot(TM) Client VM
2010-08-26 12:47:01,911 [9212250]  ERROR - llij.ide.plugins.PluginManager - Vendor: Sun Microsystems Inc.
2010-08-26 12:47:01,911 [9212250]  ERROR - llij.ide.plugins.PluginManager - OS: Windows 7
2010-08-26 12:47:01,911 [9212250]  ERROR - llij.ide.plugins.PluginManager - Last Action: EditorTab
2010-08-26 12:47:02,118 [9212457]  ERROR - llij.ide.plugins.PluginManager - tried to access method com.intellij.lang.javascript.JavaScriptCodeContextType.getLanguage(Lcom/intellij/psi/PsiFile;I)Lcom/intellij/lang/Language; from class com.intellij.lang.javascript.ActionScriptCodeContextType
java.lang.IllegalAccessError: tried to access method com.intellij.lang.javascript.JavaScriptCodeContextType.getLanguage(Lcom/intellij/psi/PsiFile;I)Lcom/intellij/lang/Language; from class com.intellij.lang.javascript.ActionScriptCodeContextType
 at com.intellij.lang.javascript.ActionScriptCodeContextType.isInContext(ActionScriptCodeContextType.java:24)
 at com.intellij.codeInsight.template.impl.TemplateManagerImpl.getContextType(TemplateManagerImpl.java:441)
 at com.intellij.codeInsight.template.impl.TemplateManagerImpl.isApplicable(TemplateManagerImpl.java:467)
 at com.intellij.codeInsight.template.impl.TemplateManagerImpl.filterApplicableCandidates(TemplateManagerImpl.java:422)
 at com.intellij.codeInsight.template.impl.TemplateManagerImpl.findMatchingTemplates(TemplateManagerImpl.java:319)
 at com.intellij.codeInsight.template.impl.TemplateManagerImpl.startTemplate(TemplateManagerImpl.java:242)
 at com.intellij.codeInsight.template.impl.TemplateManagerImpl.startTemplate(TemplateManagerImpl.java:127)
 at com.intellij.codeInsight.template.impl.editorActions.TabHandler.executeWriteAction(TabHandler.java:45)
 at com.intellij.openapi.editor.actionSystem.EditorWriteActionHandler$1.run(EditorWriteActionHandler.java:52)
 at com.intellij.openapi.application.impl.ApplicationImpl.runWriteAction(ApplicationImpl.java:754)
 at com.intellij.openapi.editor.actionSystem.EditorWriteActionHandler.execute(EditorWriteActionHandler.java:36)
 at com.intellij.openapi.editor.actionSystem.EditorAction$1.run(EditorAction.java:76)
 at com.intellij.openapi.command.impl.CommandProcessorImpl.executeCommand(CommandProcessorImpl.java:110)
 at com.intellij.openapi.editor.actionSystem.EditorAction.actionPerformed(EditorAction.java:87)
 at com.intellij.openapi.editor.actionSystem.EditorAction.actionPerformed(EditorAction.java:62)
 at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher$2.performAction(IdeKeyEventDispatcher.java:496)
 at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.processAction(IdeKeyEventDispatcher.java:536)
 at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.d(IdeKeyEventDispatcher.java:432)
 at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.dispatchKeyEvent(IdeKeyEventDispatcher.java:190)
 at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:494)
 at com.intellij.ide.IdeEventQueue.b(IdeEventQueue.java:405)
 at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:369)
 at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
 at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
 at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
 at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
 at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
 at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)