logic:iterate的问题

代码：
<%
ArrayList a = (ArrayList)request.getAttribute("list");
for (int i=0; i<a.size(); i++) {
System.out.println("####" + i + ": " + a.get(i));
}%>
<logic:iterate id="item" name="list" scope="request">
       <bean:write name="item"/>
</logic:iterate>输出如下：为什么Cannot find bean item in any scope？
####0: First
####1: Second
####2: Third
####3: Fourth
####4: Fifth
2005-12-28 10:41:17,859 ERROR [org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/cms].[jsp]] - <Servlet.service() for servlet jsp threw exception>
javax.servlet.jsp.JspException: Cannot find bean item in any scope
at org.apache.struts.taglib.TagUtils.lookup(TagUtils.java:934)
at org.apache.struts.taglib.bean.WriteTag.doStartTag(WriteTag.java:225)
at org.apache.jsp.web.main_jsp._jspx_meth_bean_write_0(org.apache.jsp.web.main_jsp:117)
at org.apache.jsp.web.main_jsp._jspService(org.apache.jsp.web.main_jsp:87)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:595)