Cannot perform web service invocation...

This web service has been working correctly for five months but began to fail intermittenly with this error, requiring a restart of the JRun server instance hosting ColdFusion 8. Any ideas?

"Error","jrpp-4","06/10/08","11:54:44","MCTDmasterEntryJ2EE",
"Cannot perform web service invocation getOrder.The fault returned when invoking the web service operation is:<br><pre>
AxisFault faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException
faultSubcode: faultString: coldfusion.xml.rpc.CFCInvocationException: [java.lang.ClassCastException : cf.egov.EXTWSsSSL.EgovOrder]
faultActor:
faultNode:
faultDetail: {}coldfusion.xml.rpc.CFCInvocationException:null {http://xml.apache.org/axis/}stackTrace:coldfusion.xml.rpc.CFCInvocationException: [java.lang.ClassCastException : cf.egov.EXTWSsSSL.EgovOrder] at coldfusion.xml.rpc.CFComponentSkeleton.__createCFCInvocationException(CFComponentSkeleton .java:723) at coldfusion.xml.rpc.CFComponentSkeleton.__cast(CFComponentSkeleton.java:408) at cf.egov.extWSsSSL.DASstorefront.getOrder(D:\JRun4\servers\94_CFMX3\cfusion\cf\egov\EXTWSs SSL\DASstorefront.cfc) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.j... The specific sequence of files included or processed is: D:\JRun4\servers\95_CFMX3\cfusion\cf\egov\EXTWSsSSL\test-getOrder().cfm, line: 49 "
coldfusion.xml.rpc.ServiceProxy$ServiceInvocationException: Cannot perform web service invocation getOrder.
at coldfusion.xml.rpc.ServiceProxy.invokeImpl(ServiceProxy.java:230)
at coldfusion.xml.rpc.ServiceProxy.invoke(ServiceProxy.java:143)
at coldfusion.runtime.CfJspPage._invoke(CfJspPage.java:2211)
at coldfusion.tagext.lang.InvokeTag.doEndTag(InvokeTag.java:417)
at cftest2dgetOrder28292ecfm715990253.runPage(D:\JRun4\servers\95_CFMX3\cfusion\cf\egov\EXTW SsSSL\test-getOrder().cfm:49)
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.ApplicationFilter.invoke(ApplicationFilter.java:279)
at coldfusion.filter.RequestMonitorFilter.invoke(RequestMonitorFilter.java:48)
at coldfusion.filter.MonitoringFilter.invoke(MonitoringFilter.java:40)
at coldfusion.filter.PathFilter.invoke(PathFilter.java:86)
at coldfusion.filter.ExceptionFilter.invoke(ExceptionFilter.java:70)
at coldfusion.filter.BrowserDebugFilter.invoke(BrowserDebugFilter.java:74)
at coldfusion.filter.ClientScopePersistenceFilter.invoke(ClientScopePersistenceFilter.java:2 8)
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.filter.RequestThrottleFilter.invoke(RequestThrottleFilter.java:126)
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:286)
at jrun.servlet.ServletEngineService.dispatch(ServletEngineService.java:543)
at jrun.servlet.jrpp.JRunProxyService.invokeRunnable(JRunProxyService.java:203)
at jrunx.scheduler.ThreadPool$ThreadThrottle.invokeRunnable(ThreadPool.java:428)
at jrunx.scheduler.WorkerThread.run(WorkerThread.java:66)