I'd rather hire someone that can give you an approximate assembly of a C function (as executed by a CPU), understand how XML documents are stored in memory for efficient querying and parsing, know how to avoid cross-domain browser security problems, have an understanding of multithreading (locks, semaphores, race conditions, etc) and an application of recursion in some other language. I wouldn't care what the knowledge is, as long as it is well rounded and demonstrates that the candidate is capable of pulling apart complex systems to gain a deep understanding in a short period of time. The ability to reason (with passion and authority) about which language or pattern is best suited to a given scenario is also vital.
Time is a terrible measure, partly because it fails to recognise that 5 years of bad/shallow/incorrect experience is worse than 2 weeks of gaining a deep understanding of a new language/pattern.