Error 500--Internal Server Error javax.servlet.ServletException: CAS authentication error: null: null at t13.edu.yale.its.tp.cas.client.filter.CASFilter.getAuthenticatedUser(CASFilter.java:296) at t13.edu.yale.its.tp.cas.client.filter.CASFilter.doFilter(CASFilter.java:242) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:60) at com.hisun.msession.http.HiMemcachedSessionFilter.doFilter(HiMemcachedSessionFilter.java:67) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:60) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3748) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3714) at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321) at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120) at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2283) at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2182) at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1493) at weblogic.work.ExecuteThread.execute(ExecuteThread.java:263) at weblogic.work.ExecuteThread.run(ExecuteThread.java:221)