Jennifer Lopez is only a week into her Vegas residency, and she?s already working her butt off ? literally. During last night?s performance of ?All I Have,? J.Lo took a final bow that no one will forget. As the singer thanked her fans and took her final bow, she suffered a wardrobe malfunction and split her pants. Yup, right up the middle. J.Lo didn?t seem to notice the breeze that most likely hit her backside.