This contribution fixes a cart problem in Google Checkout. When a successful transaction is made and the 'Continue Shopping URL' is filled in with 'gc_return.php', the cart is supposed to empty upon the shopper's return to your website. This doesn't happen and the cart is still full and the shopper has to manually empty the cart. I have included code that will empty the cart upon return. This only affects the cart if gc_return is selected.

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