Preheat oven to 375 degrees F (190 degrees C). Grease cookie sheets.
Sift together the flour, baking powder, cinnamon, ginger and salt, and set aside. In a medium bowl, cream together the margarine, brown sugar and sugar substitute. Stir in the egg and vanilla. Add sifted ingredients and stir until combined, then mix in the oats and raisins.
Drop cookies by rounded teaspoonfuls onto the prepared cookie sheets. Bake for 8 to 10 minutes in the preheated oven. Allow cookies to cool on the baking sheets.
