Drain blackberries, reserving 1/2 cup juice. Dredge blackberries in 1/2 cup flour.
Combine butter and sugar in a large mixing bowl, beating well. Add eggs, one at a time, beating well after each addition.
Combine 1/2 cups flour, cocoa, soda, and spices; add to creamed mixture alternately with blackberry juice, beginning and ending with flour mixture. Beat well after each addition. Stir in blackberries and vanilla.
Pour batter into 3 greased and floured 9 - inch round cake pans. Bake at 350° for 30 to 35 minutes or until wooden pick inserted in center comes out clean. Cool in pans 10 minutes; remove layers from pans, and let cool completely. Spread Caramel Cream Frosting between layers and on top and sides of cake.