Some lenses sold for DSLRs are based on existing film designs. There's strong evidence to suggest that the Pentax DA 35mm f2.4 is based on the FA 35mm f2, and the DA40 looks suspiciously similar to the old Pentax-M 40mm. Both have been tested on film and found perfectly usable, although you need a body capable of controlling the aperture as neither lens has an aperture ring.