Put 4 cups of milk, the sugar and the rice into the rice cooker and press start. When done, Remove inner pan from the cooker and let rest 10 minutes. In a small bowl, combine eggs, 1/4 cup milk and vanilla. Stir into rice mixture and return pot to rice cooker on warm, stirring constantly, for 2 minutes. Pour into a flat serving dish and cover with plastic wrap, folding back the corners to allow the steam to escape. When pudding has cooled to room temperature, remove plastic wrap and sprinkle surface of pudding with cinnamon. Cover tightly (with fresh wrap) and refrigerate 8 hours or overnight before serving.