For crust: In a food processor finely crush graham crackers; add sugar and process for a few seconds. Add melted butter and pulse a few times till mixed. In a 9" cheesecake pan press graham crackers on bottom and about 1 1/2" up the sides. Using two large pieces of foil, lay pan on top of foil and wrap up and around the sides of the cheesecake pan.
For batter: Mix cream cheese in large bowl with electric mixer till creamy. Add sugar, vanilla and flour; blend on medium speed till well blended. With mixture on low speed add eggs, one at a time, till just mixed. Add milk and mix just till blended (do not overmix batter!). Pour into prepared cheesecake pan. Place on a cookie sheet with sides (jellyroll pan) and pour water into the cookie sheet, being careful not to get water into the batter (this is called a water bath.) Bake at 350° for 55 to 65 minutes or until center appears nearly set when shaken. Cool cheesecake on a wire rack for 15 minutes. Using a small metal spatula, loosen crust from sides of pan. Cool 1 hour, cover and chill for at least 4 hours.
For top: beat cream cheese till creamy, add softened butter and beat at medium speed till well mixed. Melt white chocolate and add to cream cheese mixture. Add lemon juice or white chocolate liquor and beat until well mixed. Spoon onto top of cheesecake and chill for 1 hour. In microwave safe bowl heat 1 cup raspberry jam for 40 seconds or until it is soft enough to pour onto cheesecake top. Spread evenly over top. Chill till firm.