Problem with the totaling discount and taxes

[goodbreeze]

I have encountered an error with way items are totaled when a discount is applied to an item that is also taxed (within my state). This occurs with both Payment modules I use and seems to be an error with the way the totals are calculated. I am currently using the native Paypal module and the paid Paypal Pro module. Anytime an item is added to the cart that is on sale (discounted) and the customer is in the state of Florida (6% sales tax)...they are unable to checkout. Neither module will allow it. It seems to have something to do with the way the totals are calculated and what is being sent to Paypal. This is a very big problem for me as a lot of my customers are in my state. Any ideas what is going on here?