Wisk eggs and egg whites until blended. Set aside. In heavy sauce pan heat 4 cups milk with sugar, corn starch and 1/4 teas salt. Cook on med stirring until thickened and boil one minute. Remove from heat. Wisk 1/2 cup simmering milk into eggs. Pour back into saucepan. Pour into large bowl and add vanilla, nutmeg, rum and remaining 1 1/2 cups milk. Cover and chill until well chilled. Sprinkle with nutmeg to serve.