Let me (again) recommend flymake

http://flymake.sourceforge.net/

It perfoms "perl -cw" checking in the background when you are idle (not typing). Like a spell-checker it highlights your errors, so you can easily spot them (and are not forced to do explicit compiles).

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The myperl-check-syntax function could be improved by changing the last if-expression to:

  (when (not (equal (substring (buffer-string) -3 -1) "OK"))
        (switch-to-buffer "perlsyn")
        (compilation-mode)
        (goto-char (point-min))))

This enables font-locking and the "hyperlink" feature of the error lines.