Why I'm comparing these two languages? Again, I want to stress my statement, that it's easy to tell if a Java programmer is good or not. To do the same with a Perl programmer is more difficult.

Got to admit I disagree. Having seen perl code produced by job seekers (and having to deal with other peoples code in general) I find that you can very easily see whether a developer is a reasonable programmer - just as you can with any other language.

There are more differences in minor areas of style, but as long as you know perl you can understand when something is sensible.

Possibly we're talking about two different things. There is being a good programmer (being able to produce sane, comprehensible code). There is also having a knowledge of all the perl idioms and the various odd language corners.

The latter does not imply the former, and the former does not imply the latter.

I've seen code that obviously shows a deep knowledge of the various obscure corners of perl, but written in a completely non-maintainable "selfish" style. Sign of a bad programmer. Usually impossible to fix. CV goes directly to the bin.

I've also seen nice code, but that is obviously written by somebody who has come from another language. Lack of knowledge can be fixed by training. CV stays on my desk.

Obviously, the ideal is to have both :-)

Also, hopefully obviously, you never hire on code alone. Somebody can write great code and be lousy in a team.