Hey--10 years later, if anyone's still listening: I have exactly the same situation: "it will not stop down to f/2.8 when on the 'A' setting. Only goes to f/5.6 also goes past f/22 to I think f/32."

I've had this lens for 30 years. Dug it out to play with on my K-X and K-5. Same results on both cameras. Put it on my old Super Program--again, same results. Obviously problem with lens contacts, not camera. Exterior contact cleaning made no difference. I'm planning on taking off the lens mount plate and seeing if I can clean the contacts from the inside. We'll see. Along the way, I hope to get the aperture ring itself to move smoothly. It's very sticky.

Would love to rehabilitate this lens.