render the select element as a list box in ftl

[Jack Liu]

Hi, All
I took me about 1 hour to solve the problem, but failed at last.
To me, I think it's a simple question. I just want to render the select
element as a list box in ftl page and allow users to make multiple
selections from the list of options.
Code lists below:
   <tr>
        <td class="label">TestMulti</td>
        <td><select name="testmul" size="2" multiple>
                <option value="b">b</option>
                <option value="a">a</option>
        <option value="c">c</option>
                 </select>
                </td>
   </tr>
But what I get is nothing but a little box with a horizontal line in it.
When I copied it to html page, it works.

Help me please, any suggestion is appreciated.

Best Regards,

Jack Liu