MUC Service returns HTTP 500 in all request.

Just 1 hr ago I have installed MUC Service  in my openfire(ver:3.9.3). Following is my environment.

Pluging successfully deployed as of, I can see in admin console.

But no rest request is successfull. All return HTTP 500 .

http://x.x.x.x:9090/plugins/mucservice/chatrooms

GET method

Authorization : Basic YWRtaW46MTIzNDU2

I am using google chrome based Postman rest client .

In server log I get following when I fire the above rest request.

java.lang.NullPointerException

  at org.jivesoftware.openfire.plugin.MUCRoomController.getChatRooms(MUCRoomControll er.java:56)

  at org.jivesoftware.openfire.service.MUCRoomService.getMUCRooms(MUCRoomService.jav a:31)

  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.ja va:43)

  at java.lang.reflect.Method.invoke(Method.java:606)

  at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvoke rFactory.java:60)

  at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatch Provider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:18 5)

  at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.d ispatch(ResourceJavaMethodDispatcher.java:75)

  at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java: 302)

  at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule .java:108)

  at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule .java:147)

  at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourc eClassesRule.java:84)

  at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApp licationImpl.java:1542)

  at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApp licationImpl.java:1473)

  at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebAppl icationImpl.java:1419)

  at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebAppl icationImpl.java:1409)

  at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:409 )

  at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer. java:540)

  at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer. java:715)

  at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)

  at org.jivesoftware.openfire.container.PluginServlet.handleServlet(PluginServlet.j ava:316)

  at org.jivesoftware.openfire.container.PluginServlet.service(PluginServlet.java:11 1)

  at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)

  at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:547)

  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.ja va:1359)

  at org.jivesoftware.admin.PluginFilter.doFilter(PluginFilter.java:78)

  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.ja va:1330)

  at org.jivesoftware.admin.AuthCheckFilter.doFilter(AuthCheckFilter.java:164)

  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.ja va:1330)

  at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:11 8)

  at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:52)

  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.ja va:1330)

  at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:478)

  at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:119)

  at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:520)

  at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:22 7)

  at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:94 1)

  at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:409)

  at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:186 )

  at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:875 )

  at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)

  at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandler Collection.java:250)

  at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.jav a:149)

  at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)

  at org.eclipse.jetty.server.Server.handle(Server.java:349)

  at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:441)

  at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConne ction.java:919)

  at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:582)

  at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:218)

  at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:51 )

  at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.jav a:586)

  at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java :44)

  at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:598 )

  at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:533)

  at java.lang.Thread.run(Thread.java:745)

Is there anything I am doing wrong?