PREHEAT oven to 350°F if using a silver 9-inch springform pan (or to 325°F if using a dark nonstick 9-inch springrform pan). Combine graham crumbs and butter; press firmly onto bottom of pan.

BEAT cream cheese and sugar in large bowl with electric mixer on medium speed until well blended. Add eggs, 1 at a time, beating on low speed after each addition just until blended. Stir in poppy seed, lemon and lime peel and 2 Tbsp. each of the lemon and lime juice. Discard any remaining juice.

BAKE 45 to 50 min. or until centre is almost set. Run knife or metal spatula around rim of pan to loosen cake; cool before removing rim of pan. Refrigerate 3 hours or overnight. Top with whipped topping just before serving. Garnish with additional lemon and lime slices, if desired. Store leftover cheesecake in refrigerator.