java.lang.RuntimeException: This exception has no message.

java.lang.RuntimeException: 	at org.xwiki.management.internal.DefaultJMXBeanRegistration.registerMBean(DefaultJMXBeanRegistration.java:55)	at org.xwiki.velocity.internal.DefaultVelocityFactory.createVelocityEngine(DefaultVelocityFactory.java:95)	at com.xpn.xwiki.render.DefaultVelocityManager.getVelocityEngine(DefaultVelocityManager.java:211)	at org.xwiki.display.internal.AbstractDocumentTitleDisplayer.evaluateTitle(AbstractDocumentTitleDisplayer.java:168)	at org.xwiki.display.internal.AbstractDocumentTitleDisplayer.display(AbstractDocumentTitleDisplayer.java:107)	at org.xwiki.display.internal.AbstractDocumentTitleDisplayer.display(AbstractDocumentTitleDisplayer.java:50)	at org.xwiki.display.internal.DefaultDocumentDisplayer.display(DefaultDocumentDisplayer.java:80)	at org.xwiki.display.internal.DefaultDocumentDisplayer.display(DefaultDocumentDisplayer.java:38)	at org.xwiki.sheet.internal.SheetDocumentDisplayer.display(SheetDocumentDisplayer.java:111)	at org.xwiki.sheet.internal.SheetDocumentDisplayer.display(SheetDocumentDisplayer.java:50)	at org.xwiki.display.internal.ConfiguredDocumentDisplayer.display(ConfiguredDocumentDisplayer.java:67)	at org.xwiki.display.internal.ConfiguredDocumentDisplayer.display(ConfiguredDocumentDisplayer.java:41)	at com.xpn.xwiki.doc.XWikiDocument.getRenderedTitle(XWikiDocument.java:1145)	at com.xpn.xwiki.plugin.lucene.AbstractDocumentData.(AbstractDocumentData.java:109)	at com.xpn.xwiki.plugin.lucene.DocumentData.(DocumentData.java:62)	at com.xpn.xwiki.plugin.lucene.IndexUpdater.queueDocument(IndexUpdater.java:324)	at com.xpn.xwiki.plugin.lucene.IndexUpdater.onEvent(IndexUpdater.java:395)	at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:261)	at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:226)	at com.xpn.xwiki.XWiki.saveDocument(XWiki.java:1413)	at com.xpn.xwiki.plugin.scheduler.SchedulerPlugin.updateSchedulerJobClass(SchedulerPlugin.java:698)	at com.xpn.xwiki.plugin.scheduler.SchedulerPlugin.init(SchedulerPlugin.java:128)	at com.xpn.xwiki.plugin.XWikiPluginManager.initPlugin(XWikiPluginManager.java:152)	at com.xpn.xwiki.plugin.XWikiPluginManager.addPlugin(XWikiPluginManager.java:88)	at com.xpn.xwiki.plugin.XWikiPluginManager.addPlugins(XWikiPluginManager.java:116)	at com.xpn.xwiki.XWiki.preparePlugins(XWiki.java:1123)	at com.xpn.xwiki.XWiki.initXWiki(XWiki.java:793)	at com.xpn.xwiki.XWiki.(XWiki.java:738)	at com.xpn.xwiki.XWiki.getMainXWiki(XWiki.java:399)	at com.xpn.xwiki.XWiki.getXWiki(XWiki.java:486)	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:136)	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:116)	at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)	at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)	at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)	at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)	at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)	at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:538)	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1352)	at com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:120)	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323)	at org.xwiki.wysiwyg.server.filter.ConversionFilter.doFilter(ConversionFilter.java:144)	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323)	at com.xpn.xwiki.plugin.webdav.XWikiDavFilter.doFilter(XWikiDavFilter.java:66)	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323)	at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323)	at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1323)	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:476)	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:119)	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:517)	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:225)	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:937)	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:406)	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:183)	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:871)	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)	at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:247)	at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:149)	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)	at org.eclipse.jetty.server.Server.handle(Server.java:346)	at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:589)	at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:1048)	at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:601)	at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214)	at org.eclipse.jetty.server.HttpConnection.handle(HttpConnection.java:411)	at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:535)	at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:40)	at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529)	at java.lang.Thread.run(Thread.java:680)