What is this language you've been using that is so terribly different from what people learned in college that it takes the months to be effective, not even efficient? Off the top of my head, I produce.... prolog and haskell. It's very, very unlikely you'd apply for a job that was looking for those languages without realizing it.

If you know java, you know python, and you know c, and you can think in algorithmic rather than implementation terms, then you're good for pretty much anything. The hard problems are the same everywhere: cache invalidation and naming things. (I'm only partially kidding.)

EDIT: Besides, if you're hiring for 3-5 years, the advantage language knowledge grants candidates becomes minimal, and the ability to apply old lessons, to learn, to adapt, dominates. If someone has issues learning a language, there are probably more striking problems that would prevent them from getting the job anyway.