I agree that age doesn't mean experience. I work in a company with a small development team and we're all around the same age group with no young programmers.

In thios group we have a programmer in his early 40s, who has been programming for years, that I would still consider a "junior" programmer. He can usually perform a task but needs more guidance and checking than the other members if the team, most of which have been there time.

On the other side we also had a developer work there a few years back that was in his late 50s and wrote some of the worse looking code I've ever seen. Fortunatly he didn't last long and none of his code is running in production.