How to make a horizontal scrollbar in select box?

[admin]

Hi, all

I make a multiple selectbox , I hope to add horizontal scroll bar to it.

<select name="select" style="width:80" multiple size="3">
<option>aaaaaaaaaaaaaaaaaaaaaaaa</option>
<option>bbbbbbbbbbbbbbbbbbbbbbbb</option>
<option>ccccccccccccccccccccccccccccccccc</option>
<option>ddddddddddddddddddddddd</option>
</select>



I looked up in the css-sheet reference, but can not find the answer.

How can I do it with javascript?(if you know some special parameters in css-sheet, please also tell me)

Thanks

Ge