Take this with a grain of salt as I don't have experience with the 8008 however I doubt there is any way for the camera body to determine the aperture from the lens without a chip or some sort of maximum aperture info and analog feedback decoder. My Pentax 645 and 67 act the same although the latter has been modified to guess if I tell the body the maximum aperture of the lens currently on the camera. Your camera should still meter correctly if it is compatible with the attached lens - Set it to aperture priority and twiddle the aperture to see if the shutter speed changes. You should also be getting some over/under exposure indication on manual settings. If not then it is quite possible you have a dud which is where 'customer service' gets tested.

Roger.