Preheat oven to 350 degrees. Grease and flour a tube pan. Evenly spread chopped nuts around bottom of pan; set aside.
In a large bowl; combine cake and pudding mixes. Add water, dark rum, oil and eggs. With an electric mixer beat for 2 minutes. Pour batter evenly into prepared pan.
Bake for 45 - 50 minutes. The top of the cake may crack. Check with toothpick in center of cake for doneness. Cool for 30 minutes. Meanwhile prepare the glaze
In a small pan; bring to a gentle boil the sugar, butter and dark rum. Boil for 2 - 3 minutes.
Remove cake to a plate with the nuts on top. You may want to trim the bottom of the cake so it will sit flat on plate. With a fork poke cake several times for glaze to soak into. Carefully and slowly spoon the glaze over top the cake, this will take some time. Once the cake is glazed let it sit to cool completely and soak up glaze on plate. Slice and enjoy.