Dear all,
 
I have some problem to use the jython plug-in from eclipse.
I used it in the past without problem and at presant , I have the following error by trying to built the path of the jython 's project
Following error in eclipse ( version 3.1.2):
    !ENTRY org.eclipse.core.resources 4 2 2007-03-27 09:47:09.151
    !MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.core.resources".
    !STACK 0
    java.lang.NullPointerException
     at net.redrobin.eclipse.jydt.core.SystemPath.getLibraryFiles(SystemPath.java:307)
     at net.redrobin.eclipse.jydt.core.project.JythonBuilder.fullBuild(JythonBuilder.java:59)
     at net.redrobin.eclipse.jydt.core.project.JythonBuilder.build(JythonBuilder.java:218)
     at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:593)
     at org.eclipse.core.internal.runtime.InternalPlatform.run(InternalPlatform.java:1044)
     at org.eclipse.core.runtime.Platform.run(Platform.java:783)
     at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:168)
     at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:202)
     at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:231)
     at org.eclipse.core.internal.runtime.InternalPlatform.run(InternalPlatform.java:1044)
     at org.eclipse.core.runtime.Platform.run(Platform.java:783)
     at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:234)
     at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:303)
     at org.eclipse.core.internal.resources.Project.build(Project.java:106)
     at net.redrobin.eclipse.jydt.ui.project.ProjectPropertyPage$1.run(ProjectPropertyPage.java:41)
     at org.eclipse.ui.actions.WorkspaceModifyDelegatingOperation.execute(WorkspaceModifyDelegatingOperation.java:68)
     at org.eclipse.ui.actions.WorkspaceModifyOperation$1.run(WorkspaceModifyOperation.java:98)
     at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:1721)
     at org.eclipse.ui.actions.WorkspaceModifyOperation.run(WorkspaceModifyOperation.java:110)
     at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:346)
     at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:291)
     at org.eclipse.jface.dialogs.ProgressMonitorDialog.run(ProgressMonitorDialog.java:447)
     at net.redrobin.eclipse.jydt.ui.project.ProjectPropertyPage.rebuild(ProjectPropertyPage.java:50)
     at net.redrobin.eclipse.jydt.ui.project.ClassPathPropertyPage.performOk(ClassPathPropertyPage.java:38)
     at org.eclipse.jface.preference.PreferenceDialog$11.run(PreferenceDialog.java:862)
     at org.eclipse.core.internal.runtime.InternalPlatform.run(InternalPlatform.java:1044)
     at org.eclipse.core.runtime.Platform.run(Platform.java:783)
 
Any idea?
Thanks in advance,
Elisabeth