Thanks for the confirmation, sunny16. I was beginning to wonder if my camera alone was at fault.
I agree, there's still a way to use the M42 lenses--in fact, it's even more "manual" than using the green button, which really was a kind of automation, if you think about it.
It's interesting to note that all my M42 lenses are black painted or coated on the base of the lens mount. I have a couple of big lenses that do cover the pins, but apparently the coating blocks the flow of electrical current. Pentax-M and A lenses have bare chrome metal on the base, so they make good contact.
Anyway, I have an email in to Pentax describing the problem and asking if they have any solution. Maybe a software update can fix it. Or maybe a piece of aluminum foil under the edge of the lens?