Padding around select (dropdown) in IE

Question

<td style="padding:1em;">
    <select... />
</td>

In IE the dropdown is not padded by the containing cell correctly, and is 100% of the width of the cell. Is there an easy way to fix this?

Thanks

btw I've only tried in IE7, but the solution needs to work in IE8 as well. I don't really care about IE6 and before.

Edit: sorry I missed out an important part of the CSS, the select has width:100% as I want the select to fill the cell width (with a padding/margin border), not just size itself to its contents.