find ID of previous button
<p>I'm looking to find the id of the previous button. It is pretty far away - lots of table rows, tables, divs, etc. between the target and the button but I thought this would still work:</p>

<pre><code>alert( $(this).prevAll("input[type=button]").attr('id') );
</code></pre>

<p>Unfortunately this returns alerts 'undefined'. Help?</p>
