Iframe 问题

<tr>
     <td colspan="2" >
          <div class="pro_d_t">
         <div style=" width:1260px; height:28px; margin-left:10px; position:relative;">
             <div class="unsle" id="summry"><a href="#" target="Institution_monitor"  ><% if session("version")="CN" then %>Summry<% else%>Summry<% end if %></a>
                </div>
                <div class="unsle"  id="grant" ><a href="#" target="Institution_monitor"  ><% if session("version")="CN" then %>Grants<% else%>Grants<% end if %>
           </a>
             </div>
                <div class="unsle"  id="institution"><a href="index_metrix_keyword_institution.asp"  target="Institution_monitor"  ><% if session("version")="CN" then %>Institutions<% else%>Institutions<% end if %></a>
                </div>
                <div class="unsle"  id="tutor"><a href="#"  target="Institution_monitor"  ><% if session("version")="CN" then %>Researchers<% else%>Researchers<% end if %></a></div>

                <div class="sle"  id="易做图"><a href="index_metrix_keyword.asp"  target="Institution_monitor"  ><% if session("version")="CN" then %>Papers<% else%>Papers<% end if %></a></div>
             <div class="unsle" id="patent" >
                <a href="#"  target="Institution_monitor" ><% if session("version")="CN" then %>Patents<% else%>Patents<% end if %></a>
                </div>
                <div class="unsle" id="drug" >
                <a href="#"  target="Institution_monitor" ><% if session("version")="CN" then %>Drugs<% else%>Drugs<% end if %></a>
                </div>
             <div class="unsle" id="disease" >
                <a href="#"  target="Institution_monitor" ><% if session("version")="CN" then %>Diseases <% else%>Diseases<% end if %></a>
                </div>
            </div>
          </div>
      </td>
    </tr>
    <tr >
         <td colspan="2" style="padding:8px 0;" >
        <div id="preloadL" style="vertical-align:middle; width:100%; text-align:center; padding:20px auto; height:100px ">
              <img src="image/channlloading2.gif" alt="loading" width="32" height="32"/><br /><br />
             <font size="3" color="#999999" face="Arial, Helvetica, sans-serif"> Loading...</font>
             </div>
        <div style="display:none" id="load">
         <iframe  id="iframe2" name="Institution_monitor"  width="100%" height="400" frameborder="0" scrolling="no" src="index_metrix_keyword.asp"></iframe>          </div>
        </td>
    </tr>

Iframe 框架中有两个tab中有这样的代码
比如说Paper 中有  $("#Ssub", parent.document).click(function(){
alert("111")
})
   Institution中有  $("#Ssub", parent.document).click(function(){
alert("222")
}) 方法

当点击Paper tab然后点击Search就alert("111"),但是当点Institution，然后点击Search就会alert("111")alert("222")

在IE情况下是正常的，其他的浏览器都是上面的情况，求原因？

补充：VB ,  基础类