I guess another way to do something similar to what I've done here is to duplicate each light and set one copy of each light to raytrace and one copy of each light to shadow map. Then you get a shadow-mapped shadow overlaying your raytraced shadow within a single render. In a quick test, that doesn't produce quite as nice of a result as blending the two different renders on one's own, but would be a little easier to automate, and does look better than either just raytraced shadows or just mapped shadows, at least in an image like the one above. Raises the render time, of course.