Sub-total not showing discount

Okay, I have the cart setup with group pricing per item mod and I also have quantity discounts which only show for those who are not getting the special group pricing. Everything is working great together with one exception. If you order at retail price with quantity discounts, when you go to view the shopping cart, you see the sub-total as the total without the quantity discounts. Ex:

The product is $2.00 a piece.
Buying 10 gives you a 10% discount making the products then $1.80 a piece making the total of ten of them $18.00. However, you go into the shopping cart page and it shows the sub-total as $20 even though the product shows in the list as $1.80/each.

How can I get the sub-total to show WITH the discounted amount?