Heat oven to 350 degrees, Grease jelly roll pan (15x10 sheet).
Cream together butter and sugar. Add in eggs and vanilla. In a separate bowl, combine 2 1/2 cups flour, soda, salt and oatmeal. Add to butter mixture until combined. (Stir in additional flour 1/2 cup flour if dough is too sticky).
Divide dough in half. Press one half of the dough into prepared pan, speading evenly.
In a saucepan, combine raisins and the rest of the filling ingredients. Cook over medium heat until boiling. Remove from heat and let cool slightly. Spread filling over dough in pan.
Drop remaining half of dough in small crumbles all over the raisin layer. Bake 15 to 20 minutes or until golden and cooked through. Remove from oven and cool.
Combine powdered sugar, cinnamon and milk. Drizzle glaze over bars. Cut into pieces.