通过Servlet访问CMP时报错，我已经折腾了很长时间了，求大虾帮忙！！！

CMP的JNDI能够正确找到，但在调用java.util.Collection col = bookHome.findAll()时，报如下异常：
[06-6-19 23:15:38:734 CST] 00000073 ConcreteBeanC E   PMGR1014E: 获取连接工厂时发生异常：java.lang.ClassCastException: cannot cast class sample.entitybean._EJSRemoteCMPBookHome_e272c392_Stub to interface javax.resource.cci.ConnectionFactory
at com.ibm.rmi.javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:390)
at javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:157)
at com.ibm.ws.ejbpersistence.beanextensions.ConcreteBeanClassExtensionImpl.lookup(Unknown Source)
at com.ibm.ws.ejbpersistence.beanextensions.ConcreteBeanClassExtensionImpl.getConnectionFactory(Unknown Source)
at com.ibm.ws.ejbpersistence.beanextensions.ConcreteBeanClassExtensionImpl.binding(Unknown Source)
at com.ibm.ws.ejbpersistence.beanextensions.ConcreteBeanClassExtensionImpl.checkBinding(Unknown Source)
at com.ibm.ws.ejbpersistence.beanextensions.ConcreteBeanStatefulInstanceExtensionImpl.setPMHomeInfo(Unknown Source)
at com.ibm.ejs.container.ContainerManaged2_0BeanO.<init>(ContainerManaged2_0BeanO.java:160)
at com.ibm.ejs.container.ContainerManaged2_0BeanOFactory.create(ContainerManaged2_0BeanOFactory.java:42)
at com.ibm.ejs.container.EJSHome.createBeanO(EJSHome.java:836)
at com.ibm.ejs.container.EJSHome.createBeanO(EJSHome.java:975)
at com.ibm.ejs.container.EJSHome.getFinderEntityBeanO(EJSHome.java:2876)
at sample.entitybean.EJSCMPBookHomeBean_e272c392.findAll_Local(Unknown Source)
at sample.entitybean.EJSLocalCMPBookHome_e272c392.findAll(Unknown Source)
at sample.servlet.searchSevlet.performTask(searchSevlet.java:66)
at sample.servlet.searchSevlet.doPost(searchSevlet.java:56)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1212)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:629)
at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:2841)
at com.ibm.ws.webcontainer.webapp.WebGroup.handleRequest(WebGroup.java:220)
at com.ibm.ws.webcontainer.VirtualHost.handleRequest(VirtualHost.java:204)
at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:1681)
at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:77)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:421)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:367)
at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:94)
at com.ibm.ws.tcp.channel.impl.WorkQueueManager.requestComplete(WorkQueueManager.java:548)
at com.ibm.ws.tcp.channel.impl.WorkQueueManager.attemptIO(WorkQueueManager.java:601)
at com.ibm.ws.tcp.channel.impl.WorkQueueManager.workerRun(WorkQueueManager.java:934)
at com.ibm.ws.tcp.channel.impl.WorkQueueManager$Worker.run(WorkQueueManager.java:1021)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java(Compiled Code))谁知道是什么原因啊？