The camera sees so far and no farther. Render likewise displays same cutoff. Seems to be about 10 meters with Units in metric and Scale at 0.1 (decimeters). Set up a cube about 8 meters square with two walls removed. Looking into the open end on a diagonal from outside said cube the far corner looks as if sliced away with sky shown there.
Clicking N for the camera and doubling the “End” clip limit has no effect. Nor does it when I set “End” to nearer (the sky portion gets no bigger). Looking down via Num Pad 7, neither do I see either a yellow X for focal point nor the range markers. So I’m not sure if clipping is even enabled. This is in Blender 2.61 on Ubuntu Lucid.