滚动条的问题

一个Table里的若干行,大致是这样:
<table align="left" id=secTable cellSpacing=0 cellPadding=0 width=150 border=0>
     <tbody>
     <tr align=middle height=20>
                <td class=sec2 onclick=secBoard(0) width="10%"><?if ($num!=1){echo iconv("utf-8","gb2312",$GetOperSource["mms_subject"][0]);} else{echo iconv("utf-8","gb2312",$GetOperSource["mms_subject"]["string"]);}?><BR></td>
                   </tr>
     <tr align=middle height=20>
         <td class=sec1 onclick=secBoard(<?echo $i?>) width="10%"><?echo iconv("utf-8","gb2312",$GetOperSource["mms_subject"][1])?><BR></td>
            </tr>
          </tbody>
  </table>由于行数太多,所以加一个上下的滚动条.另外也需要加一个左右的滚动条.
怎么实现?谢谢!急等!