Combine cracker crumbs and margarine, stirring well. Press into bottom and up sides of a 9-inch pieplate. Bake at 350° for 8 minutes. Remove from oven, and let cool on a wire rack.
Combine pudding mix, milk, and 1/4 cup liqueur in a medium bowl, stirring with a wire whisk until smooth. Gently fold 1 cup whipped topping into pudding mixture.
Toss banana slices with remaining 1 tablespoon liqueur, and arrange over prepared crust. Spoon pudding mixture over banana slices. Cover and chill 1 1/2 hours or until set. Pipe or spoon remaining 3/4 cup whipped topping around edge of pie just before serving.