Have you specified the Request Port for each of those five WIReportServer, if not, please choose, e.g. 6422 to 6426, and have firewall ports opened.
Check out the CMS logs and see if you have the following TCP errors: [UID=0;USID=0;ID=1064777] [CORBA type=IDL:omg.org/CORBA/COMM_FAILURE:1.0;minor=1330577418;completed=1;reason=error number WSAENOBUFS] CServer::ServerIsActive: caught CORBA_SystemException for server XXXXX_CMS
Regards,
Jin-Chong