The web form on that page requires the quantity_select drop-down to be filled in. You're attempting to do that in your code by assuming the drop-down is a select element. However, it's no longer a select element. Try using Firebug to inspect the drop-down and you'll see that JavaScript has replaced the select with a complex set of nested div elements.
If you figure out how to emulate each user click on the divs for that unusual drop-down then you should be able to submit the form.
Joe Sondow
2010-01-27 12:07:29