Over at CodingHorror, Jeff riffs on problems hiring for development positions, when many interviewees aren't able to answer the most basic of code questions.
Well, I'm sure this is a common story in any skills-or-knowledge-driven industry where there's a minimum bar. For example, we have similar issues when hiring infrastructure support people. We typically advertise for senior staff with 5+ years experience.
The resumes we see are often filled with excitement-inducing hyperbole: "25 years experience on Windows NT-based systems!"; "Wrote the book on TCP/IP!"; "I like computers!"
In my experience, it's statistically likely that if someone lists strong-to-godlike TCP/IP skills, chances are they won't be able to describe a 3-way handshake.
One of my colleagues developed a pretty good canary question for people wanting to support Windows and claiming years of AD experience: "What tool do you use to manage Users and Computers in Active Directory?" He estimates 75% of interviewees fall at that hurdle.
In my last job, when it was more topical, we'd open by asking NT Domain candidates to name a couple of NetBIOS node types (yes, I was employed there a long time ago now), and for bonus points, how they were different. Anyone getting that question right was basically technically OK'd and breezed through the other questions; they just needed to impress us more than the other (two from thirty) people that got it right.
As a quick suggestion to prospective employees at any firm where I'm an inteviewer: a good portion of the interview is likely to involve going through your resume (this isn't a marketing job, you know!), so if you've put something in there, please do expect to be asked questions about it!
This post brought to you by the numbers 3 and 5, and the word "fizbuzz". Weird.