It sounds like "being a perl programmer" was one of the main characteristics you and your boss were looking for in the beginning... this is a red flag for me- if I am learning more about a job and they seem too concerned to get a "perl programmer", "java programmer", etc, I know to steer clear- it means the people designing the software and managing the projects think its hard to learn a new programming language which means they themselves probably arent good. At moment, there are plenty of programming jobs, and there seems to be a demand for perl programmers- probably because it has fallen out of favor with fresh grads and also a lot of the perl openings are for working on existing code base instead of a new shiny project. I dont blame the kids- they should go work at start ups. But they shouldnt for a moment buy into the anti-perl sentiment that pops up at software meetings and conferences (perl 6 jokes are just easy one-liners for people with no imagination).
The problem revolves around being able communicate what's going on. If you try to be helpful and informative and say something like "Object-oriented software engineer (Perl)" as your job post title, you immediately (a) get every schmuck who once did testing with Perl who is now searching for 'perl' to apply, even if they don't know any OO, thus jamming the interview process, (b) immediately get most anyone else to say "ewwwwww, Perl, I'd never be interested / I have no experience". You have to end up saying "Object-oriented software engineer in a dynamic programming language", request people in with experience in (e.g.) languages such as Ruby, Python or Perl, and only mention that it's actually in Perl further down the post once you've got their attention with the rest of it. This is a trifle more manipulative and less straightforward than a decent straightforward honest software engineer would instinctually prefer. Anyway. It's true, a couple of of the best candidates actually hired there came from Python backgrounds.
By contrast, I assume you can say something like "Object-oriented software engineer (Python)" or "Object-oriented software engineer (Ruby)" (or Frontend Engineer / Backend Engineer / etc) and not have this particular set of problems. I don't know what problems you would have, but... not those.
Now, to be fair, it worked marginally better when the company-recruiters weren't all jerks about letting us post a programming challenge with the posting (because it didn't fit in with a preexisting workflow)... which makes it easier to find the random Spanish major with decent programming instincts and a little Perl. But still.