This thread reminded me of a talk I had with my mom when I was eight. I had stolen a marble from school because I liked it so much and there was a whole basket of them, but afterwards I felt terrible and hid it. I didn't tell anyone for months. Then, one saturday I broke down and told my mom. Like U-Dog's dad, my Mom hugged me and said that it was okay, and that she was really proud of me for having such a strong conscience.
I immediately felt MUCH better...it was like a weight that I'd been carrying around with me inside my chest for months had been lifted. I bet that because of your kind, edifying response, your daughter feels the same kind of relief in knowing that you are not angry at her and (hopefully) that this one mistake does not make her a bad person.