Preheat oven to 350°. Grease and flour a 10-in. fluted tube pan. In a large bowl, combine cake mix, pudding mix, margarita mix, eggs, butter, lime juice and zest; beat on low speed for 30 seconds. Beat on medium for 2 minutes.
Transfer batter to prepared pan. Bake 45-50 minutes or until a toothpick inserted in the centre comes out clean. Cool in pan 10 minutes before removing to a wire rack to cool completely.
Meanwhile, combine glaze ingredients. Drizzle over cake.