十万火急，高手来看看，帮帮忙

我用TOMCAT5.0.16调试JSP页面时，在<title><bean:message key="title.page.welcome"/></title>这里卡住了
出现了以下异常
各种配置都是照书上写的，而且测试通过
异常代码在下面
HTTP Status 500 -

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type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:358)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


root cause

java.lang.NullPointerException
org.apache.struts.taglib.TagUtils.retrieveMessageResources(TagUtils.java:1219)
org.apache.struts.taglib.TagUtils.message(TagUtils.java:1082)
org.apache.struts.taglib.bean.MessageTag.doStartTag(MessageTag.java:226)
org.apache.jsp.welcome_jsp._jspx_meth_bean_message_0(welcome_jsp.java:115)
org.apache.jsp.welcome_jsp._jspx_meth_html_html_0(welcome_jsp.java:90)
org.apache.jsp.welcome_jsp._jspService(welcome_jsp.java:64)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


note The full stack trace of the root cause is available in the Tomcat logs.


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Apache Tomcat/5.0.16