j急！急！急！websphere服务器报错：java.lang.NoSuchMethodError: ...Ljavax/servlet/http/HttpServletRequest

错误如下，是j2ee.jar包的问题还是IE的问题呢？请大侠赐教！
[09-4-23 15:14:30:905 CST] 00000038 ServletWrappe E   SRVE0068E: 无法调用 servlet caair.front.SingleController 的 service() 方法。抛出异常：java.lang.NoSuchMethodError: pub/utils/RequestHelper.getRequest()Ljavax/servlet/http/HttpServletRequest;
at caair.front.LoginCommand.execute(LoginCommand.java:55)
at caair.front.SingleController.processRequest(SingleController.java:20)
at caair.front.SingleController.doPost(SingleController.java:39)
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.service(ServletWrapper.java:1173)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:92)
at filter.LoginFilter.doFilter(LoginFilter.java:103)
at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:142)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:77)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:626)
at com.ibm.ws.webcontainer.extension.InvokerExtensionProcessor.handleRequest(InvokerExtensionProcessor.java:248)
at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:2837)
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:1332)[09-4-23 15:14:30:920 CST] 00000038 WebApp        E   SRVE0026E: ［Servlet 错误］－［caair.front.SingleController］：java.lang.NoSuchMethodError: pub/utils/RequestHelper.getRequest()Ljavax/servlet/http/HttpServletRequest;
at caair.front.LoginCommand.execute(LoginCommand.java:55)
at caair.front.SingleController.processRequest(SingleController.java:20)
at caair.front.SingleController.doPost(SingleController.java:39)
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.service(ServletWrapper.java:1173)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:92)
at filter.LoginFilter.doFilter(LoginFilter.java:103)
at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:142)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:77)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:626)
at com.ibm.ws.webcontainer.extension.InvokerExtensionProcessor.handleRequest(InvokerExtensionProcessor.java:248)
at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:2837)
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:1332)