[yShrike]

FWIW, when I interview technical candidates, I ask technical questions until I get to the point where the candidate says "I'm not sure" or "I don't know". That helps me understand where the are in their career. If a candidate knows everything then they're not being honest with me :-)

[zwieback]

That's what I do and then pay close attention what they do when we hit that point. Ideally, the candidate will explain what they would do. If we have enough time then I want them to ask me to explain the answer to them, that tells me they are actually curious enough to fill in their gaps.