webwork配置项的顺序问题

在 xwork.xml 中配置 interceptor 时,由于配置项位置的关系得到以下错误:

WebWork Problem Report
WebWork has detected an unhandled exception:

Messages: The content of element type "package" must match "(result-types?,interceptors?,default-interceptor-ref?,default-action-ref?,global-results?,global-exception-mappings?,action*)". 
File: file:/M:/Working%20Folder/Nan/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/Nan/WEB-INF/classes/xwork.xml
Line number: 26
Column number: 15

配置文件为:

<! DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1.1.1//EN" "http://www.opensymphony.com/xwork/xwork-1.1.1.dtd" >

< xwork >
     < include  file ="webwork-default.xml" />

     < package  name ="default"  extends ="webwork-default" >
    
        
         < interceptors >
             < interceptor  name ="DBManager"  class ="com.lingsmm.common.utils.ConnectionManageInterceptor" />
            
             < interceptor-stack  name ="myDefault" >
                 < interceptor-ref  name ="params" />
                 < interceptor-ref  name ="DBManager" />
             </ interceptor-stack >
         </ interceptors >
         < default-action-ref  name ="home"   />
         < default-interceptor-ref  name ="myDefault" />

         <!--  Add your actions here  -->
         < action  name ="history"  class ="com.lingsmm.action.history.HistoryAction" >
             < result  name ="input" > /WEB-INF/pages/historyEdit.jsp </ result >
             < result  name ="login" > /WEB-INF/pages/login.jsp </ result >
             < result > /WEB-INF/pages/home.jsp </ result >
         </ action >
     </ package >
</ xwork >

在 eclipse 中编辑时,会有语法错误提示,猜想这应该是在 DTD 文件中定义的,但对 DTD 不是很熟悉,没有作进一步分析.
解决的方法是,将 default-action-ref 与 default-interceptor-ref 位置互换即可,所以认为是文档对项目节点的位置有强制要求.