smc-m lens and ist DS...

I've got myself a smc-m 50mm f.1.7, and hoping to use it on my ist DS, but when i put it on it simply doesn't work what so ever, all i see is in the screen saying "A--", i've tried turning to manual mode it still does no help...
any help would be very appreciated! thanks...

I believe you need to go into the camera menu and select :allow use of the aperture ring"

solved!! many thanks !!