Cpu Usage graph missing when using rrdtool

When using native rrdtool, the Cpu Usage graph for RHEL5 linux is missing. When I switch to jrobin, the graph is present.
The error from 'jetty.log' is:

2010-03-23 13:38:28,390 ERROR [968256266@qtp-258818643-9] log: /opennms/graph/graph.png
org.springframework.dao.DataRetrievalFailureException: Could not create graph: org.opennms.netmgt.rrd.RrdException: ERROR: Could not make sense out of ' '
; nested exception is org.opennms.netmgt.rrd.RrdException: ERROR: Could not make sense out of ' '

When I use the command string from the 'jetty.log' file, it will create the png graph properly.
It happens with both version 1.6.7 and 1.7.10.

Version: 1.7.10
Server Time: Wed Mar 24 07:53:37 PDT 2010 Client Time: Wed Mar 24 07:53:38 PDT 2010 Java Version: 1.6.0_17 Sun Microsystems Inc.
Java Virtual Machine: 14.3-b01 Sun Microsystems Inc.
Operating System: Linux 2.6.18-164.el5 (amd64) Servlet Container: jetty/6.1.22 (Servlet Spec 2.5)

rrdtool version 1.4.1

2010-03-23 13:38:28,390 ERROR [968256266@qtp-258818643-9] log: /opennms/graph/graph.png
org.springframework.dao.DataRetrievalFailureException: Could not create graph: org.opennms.netmgt.rrd.RrdException: ERROR: Could not make sense out of ' '
; nested exception is org.opennms.netmgt.rrd.RrdException: ERROR: Could not make sense out of ' '

at org.opennms.netmgt.dao.support.DefaultRrdDao.createGraph(DefaultRrdDao.java:171)
at org.opennms.web.svclayer.support.DefaultRrdGraphService.getInputStreamForCommand(DefaultRrdGraphService.java:127)
at org.opennms.web.svclayer.support.DefaultRrdGraphService.getPrefabGraph(DefaultRrdGraphService.java:172)
at sun.reflect.GeneratedMethodAccessor268.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:307)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:107)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
at $Proxy88.getPrefabGraph(Unknown Source)
at org.opennms.web.controller.RrdGraphController.handleRequestInternal(RrdGraphController.java:123)
at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:153)
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:48)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:771)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:716)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:647)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:552)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at org.extremecomponents.table.filter.AbstractExportFilter.doFilter(AbstractExportFilter.java:49)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.opennms.web.StoreRequestPropertiesFilter.doFilter(StoreRequestPropertiesFilter.java:71)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
at org.opennms.web.springframework.security.AuthFilterEnabler.doFilterHttp(AuthFilterEnabler.java:98)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
at org.springframework.security.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.ui.SessionFixationProtectionFilter.doFilterHttp(SessionFixationProtectionFilter.java:67)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.ui.ExceptionTranslationFilter.doFilterHttp(ExceptionTranslationFilter.java:101)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.providers.anonymous.AnonymousProcessingFilter.doFilterHttp(AnonymousProcessingFilter.java:105)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.wrapper.SecurityContextHolderAwareRequestFilter.doFilterHttp(SecurityContextHolderAwareRequestFilter.java:91)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.ui.basicauth.BasicProcessingFilter.doFilterHttp(BasicProcessingFilter.java:174)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.ui.AbstractProcessingFilter.doFilterHttp(AbstractProcessingFilter.java:277)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.ui.logout.LogoutFilter.doFilterHttp(LogoutFilter.java:89)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.context.HttpSessionContextIntegrationFilter.doFilterHttp(HttpSessionContextIntegrationFilter.java:235)
at org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
at org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
at org.springframework.security.util.FilterChainProxy.doFilter(FilterChainProxy.java:175)
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Caused by: org.opennms.netmgt.rrd.RrdException: ERROR: Could not make sense out of ' '

at org.opennms.netmgt.rrd.rrdtool.JniRrdStrategy.createGraphAsByteArray(JniRrdStrategy.java:398)
at org.opennms.netmgt.rrd.rrdtool.JniRrdStrategy.createGraph(JniRrdStrategy.java:371)
at org.opennms.netmgt.rrd.QueuingRrdStrategy.createGraph(QueuingRrdStrategy.java:892)
at org.opennms.netmgt.dao.support.DefaultRrdDao.createGraph(DefaultRrdDao.java:169)