Prehat oven to 325 degrees F. Grease and flour a 10" tube or 12" Bundt pan. Sprinkle nuts over bottom of pan. In large mixing bowl combine cake mix, eggs, ½ cup cold water, oil, and ½ cup rum. Mix well. Pour into prepared pan over nuts. Bake about 55 minutes until golden brown and the middle tests done with wooden toothpick. Cool in pan on wire rack 10 minutes and prepare glaze while itâs cooling. After cake has cooled slightly invert onto serving platter and prick top all over with toothpick. Spoon and brush glaze evenly over top and sides (I use a turkey baster to reach all surfaces easily.) At first the hot syrup will pool in middle and at bottom edges but as it cools the syrup gets thicker and if you keep spooning or basting it back up to top, eventually all the syrup will absorb into cake. GLAZE: Melt butter in saucpan over medium heat; add 1/4 cup water, and sugar. Bring to a boil, reduce heat as needed to boil gently for 5 minutes, stirring constantly. Remove from heat. Stir in rum. Optionally decorate border with sugar frosting or whipped cream.