eclipse plugin can't save settings

not sure if it is a plugin problem or a intellij problem. i imported a porject from a eclipse project.


2011-11-29 15:14:02,790 [7177361]  ERROR - a.eclipse.conversion.EPathUtil - Vendor: Sun Microsystems Inc.
2011-11-29 15:14:02,790 [7177361]  ERROR - a.eclipse.conversion.EPathUtil - OS: Linux
2011-11-29 15:14:02,790 [7177361]  ERROR - a.eclipse.conversion.EPathUtil - Last Action: Vcs.ShowTabbedFileHistory
2011-11-29 15:14:02,796 [7177367]   INFO - ellij.project.impl.ProjectImpl - Unable to save plugin settings
com.intellij.diagnostic.PluginException: Argument 1 for @NotNull parameter of com/intellij/openapi/vfs/VfsUtil.isAncestor must not be null [Plugin: org.jetbrains.idea.eclipse]
    at com.intellij.openapi.components.impl.stores.ComponentStoreImpl.startSave(ComponentStoreImpl.java:125)
    at com.intellij.openapi.components.impl.stores.ModuleStoreImpl.startSave(ModuleStoreImpl.java:44)
    at com.intellij.openapi.components.impl.stores.ProjectWithModulesStoreImpl$ProjectWithModulesSaveSession.<init>(ProjectWithModulesStoreImpl.java:87)
    at com.intellij.openapi.components.impl.stores.ProjectWithModulesStoreImpl.createSaveSession(ProjectWithModulesStoreImpl.java:78)
    at com.intellij.openapi.components.impl.stores.ComponentStoreImpl.startSave(ComponentStoreImpl.java:111)
    at com.intellij.openapi.components.impl.stores.ProjectWithModulesStoreImpl.startSave(ProjectWithModulesStoreImpl.java:36)
    at com.intellij.openapi.components.impl.ComponentManagerImpl.doSave(ComponentManagerImpl.java:714)
    at com.intellij.openapi.project.impl.ProjectImpl.save(ProjectImpl.java:292)
    at com.intellij.ide.SaveAndSyncHandler.saveProjectsAndDocuments(SaveAndSyncHandler.java:127)
    at com.intellij.ide.SaveAndSyncHandler$3.onFrameDeactivated(SaveAndSyncHandler.java:84)
    at com.intellij.ide.FrameStateManagerImpl.fireDeactivationEvent(FrameStateManagerImpl.java:100)
    at com.intellij.ide.FrameStateManagerImpl.access$500(FrameStateManagerImpl.java:31)
    at com.intellij.ide.FrameStateManagerImpl$2$1.run(FrameStateManagerImpl.java:72)
    at com.intellij.util.Alarm$Request$1.run(Alarm.java:229)
    at com.intellij.openapi.application.impl.LaterInvocator$FlushQueue.run(LaterInvocator.java:332)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
    at java.awt.EventQueue.access$000(EventQueue.java:84)
    at java.awt.EventQueue$1.run(EventQueue.java:602)
    at java.awt.EventQueue$1.run(EventQueue.java:600)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
    at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:662)
    at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:515)
    at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:411)
    at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:369)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Caused by: java.lang.IllegalArgumentException: Argument 1 for @NotNull parameter of com/intellij/openapi/vfs/VfsUtil.isAncestor must not be null
    at com.intellij.openapi.vfs.VfsUtil.isAncestor(VfsUtil.java)
    at org.jetbrains.idea.eclipse.conversion.EPathUtil.collapse2EclipsePath(EPathUtil.java:221)
    at org.jetbrains.idea.eclipse.conversion.EclipseClasspathWriter.createClasspathEntry(EclipseClasspathWriter.java:136)
    at org.jetbrains.idea.eclipse.conversion.EclipseClasspathWriter.writeClasspath(EclipseClasspathWriter.java:61)
    at org.jetbrains.idea.eclipse.config.EclipseClasspathStorageProvider$EclipseClasspathConverter.setClasspath(EclipseClasspathStorageProvider.java:216)
    at com.intellij.openapi.roots.impl.storage.ClasspathStorage.setState(ClasspathStorage.java:157)
    at com.intellij.openapi.roots.impl.storage.ClasspathStorage$2.setState(ClasspathStorage.java:173)
    at com.intellij.openapi.components.impl.stores.StateStorageManagerImpl$MyExternalizationSession.setState(StateStorageManagerImpl.java:461)
    at com.intellij.openapi.components.impl.stores.ComponentStoreImpl.commitPersistentComponent(ComponentStoreImpl.java:158)
    at com.intellij.openapi.components.impl.stores.ComponentStoreImpl.access$600(ComponentStoreImpl.java:44)
    at com.intellij.openapi.components.impl.stores.ComponentStoreImpl$SaveSessionImpl.commit(ComponentStoreImpl.java:478)
    at com.intellij.openapi.components.impl.stores.ComponentStoreImpl.startSave(ComponentStoreImpl.java:113)
    ... 32 more