MarketPress add_to_cart ajax action question

Hi,

Consider the following:
Products:
Item 1
Item 2
Item 3

If I click the "add_to_cart" button of each item separately, which is only click on the other Item add_to_cart button after the previous one has executed. It works perfectly fine.

But if I continuously click the add_to_cart button one after another without waiting one to complete, only the last item click will be added to the cart.

Any advice?