This is what I found...
<div>
<input type="hidden" name="__EVENTTARGET" id="__EVENTTARGET" value="btin" />
<input type="hidden" name="__EVENTARGUMENT" id="__EVENTARGUMENT" value="" /><input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPDwULLTIxNDY5ODU5NTcPZBYCAgEPZBYCAgkPDxYCHgdWaXNpYmxlaGRkGAEFHl9fQ29udHJvbHNSZXF1aXJlUG9zdEJhY2tLZXlfXxYBBQRidGlu9+TYw0sfl63jhQaG3vvV1MBXVWIJc+Kd0I+JN/gHnng=" />
</div>
<script type="text/javascript">
//<![CDATA[
var theForm = document.forms['form2'];
if (!theForm) {
theForm = document.form2;
}
function __doPostBack(eventTarget, eventArgument) {
if (!theForm.onsubmit || (theForm.onsubmit() != false)) {
theForm.__EVENTTARGET.value = eventTarget;
theForm.__EVENTARGUMENT.value = eventArgument;
theForm.submit();
}
}
//]]>
</script>
<div>
<input type="hidden" name="__VIEWSTATEGENERATOR" id="__VIEWSTATEGENERATOR" value="881C1645" />
<input type="hidden" name="__EVENTVALIDATION" id="__EVENTVALIDATION" value="/wEdAAXP2rylwL5U3oJ9bDnttCYzoiuHG1JM7SRvG7QXShBtUkHzh8XRDl787XQs/G4KtMFFNAdTqhzzY4gUBKAQB/9ZsbvItzGNuOxxNBTFmN4z7vd61t4TsFk7w6TQQ6ljIgyk/d8tg8q7AhxCLskGhhmZ" />
</div>