Apply copon to highest price one

[pchojar]

My coupons are configured to apply towards 100% of product value and they are valid for multiple items.
If I have two products in my shopping cart, it seems to be applying the coupon towards the lowest value product. Also if I have three products in the cart and apply three coupons the total should be zero. It actually deducts the lowest price from all three products, instead of making the total zero.

How can I fix that?