NoClassDefFound Error in Group Chat -> Room Summary ver 3.4.3

Anyone got a clue why I’d be getting this one? TIA!

Exception:

java.lang.NoClassDefFoundError: org/jivesoftware/openfire/admin/muc_002droom_002dsummary_jsp$1
     at org.jivesoftware.openfire.admin.muc_002droom_002dsummary_jsp._jspService(muc_002droom_002dsummary_jsp.java:82)
     at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
     at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487)
     at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1093)
     at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:118)
     at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:52)
     at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)
     at org.jivesoftware.util.LocaleFilter.doFilter(LocaleFilter.java:65)
     at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)
     at org.jivesoftware.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:41)
     at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)
     at org.jivesoftware.admin.PluginFilter.doFilter(PluginFilter.java:69)
     at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)
     at org.jivesoftware.admin.AuthCheckFilter.doFilter(AuthCheckFilter.java:98)
     at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)
     at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:360)
     at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
     at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181)
     at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:712)
     at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405)
     at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:211)
     at org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
     at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:139)
     at org.mortbay.jetty.Server.handle(Server.java:313)
     at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:506)
     at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:830)
     at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:514)
     at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211)
     at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:381)
     at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:396)
     at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:442)