The camera will confirm focus, even with a manual lens, I use manual lenses on my K20 all the time. One trick, you might want to experiment with, is the 'catch in focus' feature on you camera, it's basically a way for Pentax to do autofocus with a manual lens. To do this, on the K10:

1. Set the autofocus level on the camera to AF-S
2. Focus slightly behind or in front of the subject, keeping it blurry
3. Press the shutter release fully
4. Manually adjust focus until the subject becomes clear, the camera will trip the shutter when focus is acquired (you'll see the focus hex and hear the beep).

The K20 has a menu option to turn this on or off, but I don't think the K10 has that. Anyways, it only works with manual focus lenses.

The camera will confirm focus, even with a manual lens, I use manual lenses on my K20 all the time. One trick, you might want to experiment with, is the 'catch in focus' feature on your camera, it's basically a way for Pentax to do autofocus with a manual lens. To do this, on the K10:

1. Set the autofocus level on the camera to AF-S
2. Focus slightly behind or in front of the subject, keeping it blurry
3. Press the shutter release fully
4. Manually adjust focus until the subject becomes clear, the camera will trip the shutter when focus is acquired (you'll see the focus hex and hear the beep).

The K20 has a menu option to turn this on or off, but I don't think the K10 has that. Anyways, it only works with manual focus lenses.