pager question in struts2+Pager Taglib2

[red phoenix]

I use struts2.0.14 and Pager Taglib2.0, I want to use Pager Taglib2.0 in
struts2

In action file
public String search() throws Exception{
  System.out.println("call search");
  ....
  request.setAttribute("index","center");
  request.setAttribute("pageUrl","/test/search.action");
  ....
  return SUCCESS;
}

in xml file
<action name="search.action" class="Test.MyAction" method="search">
   <result>/test/mypage.jsp</result>
  </action>

In jsp file
<s:form action="search.action">
<pg:pager
   items="${request.items}"
   index="center"
   maxPageItems="${request.maxPageItems}"
   maxIndexPages="${request.maxIndexPages}"
   isOffset="true"
   export="offset,currentPageNumber=pageNumber"
   scope="request">

<pg:prev export="pageUrl" ifnull="<%= true %>">
  <% if (pageUrl != null) { %>
    <td align=right><A HREF="<%= pageUrl %>"><IMG
      SRC=http://www.google.com/nav_previous.gif alt="" border=0><br>
    <b>Previous</b></A></td>
  <% } else { %>
    <td><IMG SRC=http://www.google.com/nav_first.gif alt="" border=0></td>
  <% } %>
</pg:prev>
<pg:pages>
  <% if (pageNumber == currentPageNumber) { %>
    <td><IMG SRC=http://www.google.com/nav_current.gif alt=""><br>
    <font color=#A90A08><%= pageNumber %></font></td>
  <% } else { %>
    <td><A HREF="<%= pageUrl %>"><IMG
      SRC=http://www.google.com/nav_page.gif alt="" border=0><br>
    <%= pageNumber %></A></td>
  <% } %>
</pg:pages>
<pg:next export="pageUrl" ifnull="<%= true %>">
  <% if (pageUrl != null) { %>
    <td><A HREF="<%= pageUrl %>"><IMG
      SRC=http://www.google.com/nav_next.gif alt="" border=0><br>
    <b>Next</b></A></td>
  <% } else { %>
    <td><IMG SRC=http://www.google.com/nav_last.gif alt="" border=0></td>
  <% } %>
</pg:next>

When I run above code,it can run well,but when I click next page
button,tomcat raise a warning message:
Warn: No configuration found for the specified action: 'search' in
namespace: '/test/mypage'. Form action defaulting to 'action' attribute's
literal value.

Why raise above warning message? I guess when click next button,it should
call action search method,why it don't call it? How to correct above code?

Thanks!