For crust:
Preheat oven to 375°F. Butter 13x9x2-inch glass baking dish. Combine first 4 ingredients in medium bowl. Add butter; rub with fingertips until mixture resembles coarse meal. Press half of crumb mixture onto bottom of prepared pan. Bake crust until light brown, about 15 minutes. Cool slightly.
For filling:
Mix blueberries, jam, flour and lemon peel in bowl.
Spread filling over crust. Sprinkle remaining crumb mixture over. Bake until topping is golden, about 35 minutes. Cool in pan. Cut into squares and serve.