Preheat oven to 350 degrees F. Grease pan. In a medium bowl, mix graham cracker crumbs with melted butter. Press into bottom of springform pan. In a large bowl, mix cream cheese with sugar until smooth. Blend in milk, and then mix in the eggs one at a time, mixing just enough to incorporate. Mix in sour cream, vanilla and flour until smooth. Pour filling into prepared crust. Bake 1 hour. Turn the oven off, and let cake cool in oven with the door closed for 5 to 6 hours; this prevents cracking. Chill in refrigerator until serving.