In a small pan mix together raisins, dates, and water. Bring to a boil for 3 minutes, then cool. In a medium bowl, stir together oil, eggs, vanilla, artificial sweetener, flour, baking soda, and oats. Add the boiled mixture to this, stir, and refrigerate overnight.
Preheat oven to 350 degrees F (175 degrees C).
Drop cookies from a teaspoon onto a cookie sheet and bake for 10 minutes in the preheated oven.