CF8 enabling debug output fails

In the CF8 administrator I set a debug IP address and then selected the "Enable Request Debugging Output " so that I could get some on-screen debug information for an application I'm working on. It must be due to some configuration problem. Not sure. Below is the error message:

500

ROOT CAUSE:
coldfusion.runtime.UndefinedVariableException: Variable CFDEBUGGER is undefined.
at coldfusion.runtime.CfJspPage._get(CfJspPage.java:315)
at coldfusion.runtime.CfJspPage._get(CfJspPage.java:277)
at cfclassic2ecfm422684228._factor18(C:\CFusion\wwwroot\WEB-INF\debug\classic.cfm:31)
at cfclassic2ecfm422684228._factor26(C:\CFusion\wwwroot\WEB-INF\debug\classic.cfm:10)
at cfclassic2ecfm422684228.runPage(C:\CFusion\wwwroot\WEB-INF\debug\classic.cfm:1)
at coldfusion.runtime.CfJspPage.invoke(CfJspPage.java:192)
at coldfusion.tagext.lang.IncludeTag.doStartTag(IncludeTag.java:366)
at coldfusion.filter.CfincludeFilter.invoke(CfincludeFilter.java:65)
at coldfusion.filter.CfincludeFilter.include(CfincludeFilter.java:33)
at coldfusion.filter.BrowserDebugFilter.invoke(BrowserDebugFilter.java:94)
at coldfusion.filter.ClientScopePersistenceFilter.invoke(ClientScopePersistenceFilter.java:28)
at coldfusion.filter.BrowserFilter.invoke(BrowserFilter.java:38)
at coldfusion.filter.NoCacheFilter.invoke(NoCacheFilter.java:46)
at coldfusion.filter.GlobalsFilter.invoke(GlobalsFilter.java:38)
at coldfusion.filter.DatasourceFilter.invoke(DatasourceFilter.java:22)
at coldfusion.CfmServlet.service(CfmServlet.java:175)
at coldfusion.bootstrap.BootstrapServlet.service(BootstrapServlet.java:89)
at jrun.servlet.FilterChain.doFilter(FilterChain.java:86)
at coldfusion.monitor.event.MonitoringServletFilter.doFilter(MonitoringServletFilter.java:42)
at coldfusion.bootstrap.BootstrapFilter.doFilter(BootstrapFilter.java:46)
at jrun.servlet.FilterChain.doFilter(FilterChain.java:94)
at jrun.servlet.FilterChain.service(FilterChain.java:101)
at jrun.servlet.ServletInvoker.invoke(ServletInvoker.java:106)
at jrun.servlet.JRunInvokerChain.invokeNext(JRunInvokerChain.java:42)
at jrun.servlet.JRunRequestDispatcher.invoke(JRunRequestDispatcher.java:284)
at jrun.servlet.ServletEngineService.dispatch(ServletEngineService.java:543)
at jrun.servlet.jrpp.JRunProxyService.invokeRunnable(JRunProxyService.java:203)
at jrunx.scheduler.ThreadPool$DownstreamMetrics.invokeRunnable(ThreadPool.java:320)
at jrunx.scheduler.ThreadPool$ThreadThrottle.invokeRunnable(ThreadPool.java:428)
at jrunx.scheduler.ThreadPool$UpstreamMetrics.invokeRunnable(ThreadPool.java:266)
at jrunx.scheduler.WorkerThread.run(WorkerThread.java:66)


javax.servlet.ServletException: ROOT CAUSE:
coldfusion.runtime.UndefinedVariableException: Variable CFDEBUGGER is undefined.
at coldfusion.runtime.CfJspPage._get(CfJspPage.java:315)
at coldfusion.runtime.CfJspPage._get(CfJspPage.java:277)
at cfclassic2ecfm422684228._factor18(C:\CFusion\wwwroot\WEB-INF\debug\classic.cfm:31)
at cfclassic2ecfm422684228._factor26(C:\CFusion\wwwroot\WEB-INF\debug\classic.cfm:10)
at cfclassic2ecfm422684228.runPage(C:\CFusion\wwwroot\WEB-INF\debug\classic.cfm:1)
at coldfusion.runtime.CfJspPage.invoke(CfJspPage.java:192)
at coldfusion.tagext.lang.IncludeTag.doStartTag(IncludeTag.java:366)
at coldfusion.filter.CfincludeFilter.invoke(CfincludeFilter.java:65)
at coldfusion.filter.CfincludeFilter.include(CfincludeFilter.java:33)
at coldfusion.filter.BrowserDebugFilter.invoke(BrowserDebugFilter.java:94)
at coldfusion.filter.ClientScopePersistenceFilter.invoke(ClientScopePersistenceFilter.java:28)
at coldfusion.filter.BrowserFilter.invoke(BrowserFilter.java:38)
at coldfusion.filter.NoCacheFilter.invoke(NoCacheFilter.java:46)
at coldfusion.filter.GlobalsFilter.invoke(GlobalsFilter.java:38)
at coldfusion.filter.DatasourceFilter.invoke(DatasourceFilter.java:22)
at coldfusion.CfmServlet.service(CfmServlet.java:175)
at coldfusion.bootstrap.BootstrapServlet.service(BootstrapServlet.java:89)
at jrun.servlet.FilterChain.doFilter(FilterChain.java:86)
at coldfusion.monitor.event.MonitoringServletFilter.doFilter(MonitoringServletFilter.java:42)
at coldfusion.bootstrap.BootstrapFilter.doFilter(BootstrapFilter.java:46)
at jrun.servlet.FilterChain.doFilter(FilterChain.java:94)
at jrun.servlet.FilterChain.service(FilterChain.java:101)
at jrun.servlet.ServletInvoker.invoke(ServletInvoker.java:106)
at jrun.servlet.JRunInvokerChain.invokeNext(JRunInvokerChain.java:42)
at jrun.servlet.JRunRequestDispatcher.invoke(JRunRequestDispatcher.java:284)
at jrun.servlet.ServletEngineService.dispatch(ServletEngineService.java:543)
at jrun.servlet.jrpp.JRunProxyService.invokeRunnable(JRunProxyService.java:203)
at jrunx.scheduler.ThreadPool$DownstreamMetrics.invokeRunnable(ThreadPool.java:320)
at jrunx.scheduler.ThreadPool$ThreadThrottle.invokeRunnable(ThreadPool.java:428)
at jrunx.scheduler.ThreadPool$UpstreamMetrics.invokeRunnable(ThreadPool.java:266)
at jrunx.scheduler.WorkerThread.run(WorkerThread.java:66)

at coldfusion.monitor.event.MonitoringServletFilter.doFilter(MonitoringServletFilter.java:70)
at coldfusion.bootstrap.BootstrapFilter.doFilter(BootstrapFilter.java:46)
at jrun.servlet.FilterChain.doFilter(FilterChain.java:94)
at jrun.servlet.FilterChain.service(FilterChain.java:101)
at jrun.servlet.ServletInvoker.invoke(ServletInvoker.java:106)
at jrun.servlet.JRunInvokerChain.invokeNext(JRunInvokerChain.java:42)
at jrun.servlet.JRunRequestDispatcher.invoke(JRunRequestDispatcher.java:284)
at jrun.servlet.ServletEngineService.dispatch(ServletEngineService.java:543)
at jrun.servlet.jrpp.JRunProxyService.invokeRunnable(JRunProxyService.java:203)
at jrunx.scheduler.ThreadPool$DownstreamMetrics.invokeRunnable(ThreadPool.java:320)
at jrunx.scheduler.ThreadPool$ThreadThrottle.invokeRunnable(ThreadPool.java:428)
at jrunx.scheduler.ThreadPool$UpstreamMetrics.invokeRunnable(ThreadPool.java:266)
at jrunx.scheduler.WorkerThread.run(WorkerThread.java:66)


Any ideas how to fix this? Is it some missing setting in the JVM parameters?