Place cranberries in an airtight container and cover with Kahlua. Refrigerate overnight or for 24 hours. Remove cranberries from refrigerator and ice cream from freezer, allowing it to soften slightly. Dust a plate with cinnamon, and with a damp paper towel wet the rim of 4 martini glasses and coat the rim of the glasses with the cinnamon. Place 2 scoops of ice cream in each glass. Spoon 3 tablespoons of cranberries over the ice cream in each glass. Pour leftover Kahlua over the ice cream. Let ice cream stand to desired softness. Dust with cinnamon and serve. Serves 4.