js隐藏嵌入表边框

<script type="text/javascript" src="jquery.min.js">
</script>
<script type="text/javascript">

function jq_hide_tb_border( tb_id)
{
    var tb=jQuery(tb_id);
    tb.css("border","0");
    jQuery("tr:first",tb ).find("td").css("border-top","0");
    jQuery("tr:last",tb ).find("td").css("border-bottom","0");
    jQuery("tr td:first-child",tb).css("border-left","0");
    jQuery("tr td:last-child",tb).css("border-right","0");
}

$(function(){
    jq_hide_tb_border('#innertable');
});
</script>

HTML:

<table width="878" height="383" border="1" cellpadding="0" cellspacing="0" bordercolor="#000000"
 style="border:solid 1px black; border-collapse:collapse">
  <tr>
    <td width="422" height="62">&nbsp;</td>
    <td width="450">&nbsp;</td>
  </tr>
  <tr>
    <td height="238">
    
    <table id="innertable" width="100%" height="300" border="1" cellpadding="0" cellspacing="0"  bordercolor="#000000" 
    style="border:solid 1px black; border-collapse:collapse">
      <tr>
        <td>sdf</td>
        <td>fsd</td>
      </tr>
      <tr>
        <td>sdfsd</td>
        <td>fsdf</td>
      </tr>
      <tr>
        <td>sdfsd</td>
        <td>fsdf</td>
      </tr>
    </table></td>
    <td>&nbsp;</td>
  </tr>
  <tr>
    <td>&nbsp;</td>
    <td>&nbsp;</td>
  </tr>
</table>