Heat oven to 350 degrees. Prepare, bake and cool cake mix as directed on package for 2 - 9 inch round cake layers. Place cake layers, top sides up, in 2 clean 9-inch round cake pans. Pierce cake with large fork at 1/2 inch intervals. STIR 1 cup of the boiling water into each flavor of gelatin in separate bowls for 2 minutes or until dissolved. Carefully pour red gelatin over 1 cake layer and lime gelatin over second cake layer, refrigerate 3 hours. Dip 1 cake pan in warm water 10 seconds. Unmold second cake layer. Carefully place on first layer. Frost top sides of cake with remaining frosting. REFRIGERATE 1 hour or until ready to serve. Decorate as desired.