Ajax add to cart button on product single

Can figure out how to make add to cart ajax button work on single product page after theme overhide

I’ve used to use this hack to make add to cart ajax button work on single product page

http://wordpress.stackexchange.com/questions/55813/the-hook-for-the-ajax-add-to-cart-button

Does anybody know like to make it work?

http://wordpress.org/extend/plugins/woocommerce/