Position rack in center of oven and preheat to 350 degrees. Lightly butter 9 or 10 inch springform pan.
For crust: Combine walnuts, graham cracker crumbs and butter. Press compactly onto bottom of pan.
For filling: Beat cream cheese in large bowl of electric mixer until smooth. Add eggs, sugar, lemon juice and vanilla. Beat thoroughly. Spoon over crust.
Set pan on baking sheet to catch any batter that may drip out. Bake 10-inch cake 40 to 45 minutes. Bake 9-inch cake 50 to 55 minutes. Cake may rise slightly and crack in several areas; it will settle again. Cracks will minimize. Remove from oven and let cool. Refrigerate overnight. Using knife loosen cake from pan, remove springform.