if someone on low income purchases a prius and files for the 2007 tax credit.. say you owe the irs 1100.00 for the year and you had 1200.00 withheld, the irs refunds you $100 what happens with the tax credit ?? do you get your 1100.00 back? (or whatever the hybrid tax break was @ time of purchase) or does the hybrid refund only cover if you owe taxes