Update cost before shipping on checkout page

Cost before shipping price does not update when using discount code.

This is confusing to my customers. They don’t think the code is working and don’t know to scroll to the bottom of the page to see the Review and Purchase area. Therefore, they abandon the shopping system altogether.

http://www.sayitinthread.com

use coupon code: facebook

http://wordpress.org/plugins/wp-e-commerce/