Iframe 问题

[许晨辰]

<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="paper"><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？