webwork验证问题

在运行验证的时候，总是提示这个错误
javax.servlet.ServletException: Document root element "xxwork", must match DOCTYPE root "validators". - file:///D:/Program%20Files/MyEclipse%206.0/myeclipse/eclipse/plugins/com.genuitec.eclipse.easie.tomcat.myeclipse_6.0.0.zmyeclipse60020070820/tomcat/bin/com/lichong/action/allbook/addbookAction-validation.xml:5:9
com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:285)
com.opensymphony.webwork.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:202)
这是为什么？那里错了？
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addbookAction-validation.xml如下
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE validators PUBLIC
"-//OpenSymphony Group//XWork Validator 1.0//EN"
"http://www.opensymphony.com/xwork/xwork-validator-1.0.dtd">
<xxwork>
<validators>
<field name="book.bookname">
<field-validator type="requiredstring">
<message>请填写书名</message>
</field-validator>
</field>
<field name="book.bookpeople">
<field-validator type="requiredstring">
<message>请填写作者</message>
</field-validator>
</field>
</validators>
</xxwork>
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xwork.xml如下
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1.0//EN"
"http://www.opensymphony.com/xwork/xwork-1.0.dtd"><xwork>
<include file="webwork-default.xml"></include>
<package name="default" extends="webwork-default">
<action name="addbook" class="addbookAction" method="addbook">
<result name="success" type="redirect">index.action</result>
<result name="input" type="dispatcher">
                <param name="location">addbook.jsp</param>
            </result>
            <interceptor-ref name="validationWorkflowStack" /> 
</action>
</package>
</xwork>
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addbookAction如下import java.util.List;
import javax.servlet.http.HttpServletRequest;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.li.dao.BaseDao;
import com.li.dao.BookAllDao;
import com.li.dao.model.HtdBookAll;
import com.opensymphony.xwork.ActionSupport;@SuppressWarnings("serial")
public class addbookAction extends ActionSupport {


protected HtdBookAll book; public HtdBookAll getBook() throws Exception {
return book;
} public void setBook(HtdBookAll book) throws Exception {
this.book = book;
} public String addbook() throws Exception {
return SUCCESS;
}}
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jsp页面如下
<%@ page language="java" pageEncoding="UTF-8"%>
<%@ taglib prefix="ww" uri="/webwork" %>
<html>
  <head>
    <title>添加图书</title>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
  </head>
  <body leftmargin="0" topmargin="0" marginwidth="0" marginheight="0" scroll="no">
  <table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
    <tr
      <td valign="top">
            <form id="form1" name="form1" method="post" action="addbook.action">
            <table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0" id="content">                    
              <tr> 
                <td width="24%" height="30" class="bodyTextBold">书名</td>
                <td width="56%" height="30"><input type="text" name="book.bookname" id="book.bookname" value="<ww:property value="book.bookname"/>"/></td>
                <td width="20%" height="30">&nbsp;
                <font color="red"><ww:property value="fieldErrors.get('book.bookname').get(0)"/></font>
    <ww:if test="errorNameMessage!=null">
       <font color="red">
         <ww:property value="errorNameMessage"/>
       </font>
    </ww:if>
                </td>
              </tr>
              <tr> 
                <td width="24%" height="30" nowrap class="bodyTextBold">作者</td>
                <td width="56%" height="30"><input type="text" name="book.bookpeople" id="book.bookpeople" value="<ww:property value="book.bookpeople"/>"/></td>
                <td width="20%" height="30">&nbsp;
                <font color="red"><ww:property value="fieldErrors.get('book.bookpeople').get(0)"/></font>
    <ww:if test="errorNameMessage!=null">
       <font color="red">
         <ww:property value="errorNameMessage"/>
       </font>
    </ww:if>
                </td>
              </tr>
              <tr><td colspan="3" height="20">&nbsp;</td></tr>
              <tr> 
                <td width="24%" height="30" nowrap class="bodyTextBold">&nbsp;</td>
                <td width="56%" height="30"><input type="submit" name="button" id="button" value="提交" /></td>
                <td width="20%" height="30">&nbsp;</td>
              </tr>
            </table>
           </form>
        </td>
    </tr>
  </table>
</body>
</html>
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validators.xml如下
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1.0//EN" 
"http://www.opensymphony.com/xwork/xwork-1.0.dtd">
<validators>
<validator name="required"
class="com.opensymphony.xwork.validator.validators.RequiredFieldValidator" />
<validator name="requiredstring"
class="com.opensymphony.xwork.validator.validators.RequiredStringValidator" />
<validator name="int"
class="com.opensymphony.xwork.validator.validators.IntRangeFieldValidator" />
<validator name="double"
class="com.opensymphony.xwork.validator.validators.DoubleRangeFieldValidator" />
<validator name="date"
class="com.opensymphony.xwork.validator.validators.DateRangeFieldValidator" />
<validator name="expression"
class="com.opensymphony.xwork.validator.validators.ExpressionValidator" />
<validator name="fieldexpression"
class="com.opensymphony.xwork.validator.validators.FieldExpressionValidator" />
<validator name="email"
class="com.opensymphony.xwork.validator.validators.EmailValidator" />
<validator name="url"
class="com.opensymphony.xwork.validator.validators.URLValidator" />
<validator name="visitor"
class="com.opensymphony.xwork.validator.validators.VisitorFieldValidator" />
<validator name="conversion"
class="com.opensymphony.xwork.validator.validators.ConversionErrorFieldValidator" />
<validator name="stringlength"
class="com.opensymphony.xwork.validator.validators.StringLengthFieldValidator" />
<validator name="regex"
class="com.opensymphony.xwork.validator.validators.RegexFieldValidator" />
</validators>