Especially from a language that has specially targetted application area, to a general language like Perl. The need or motivation of such coversion, most likely, indicates that the choice of Lisp was wrong at the beginning.

I know many Lisp developers (myself included) who would disagree that it's aimed at a particular application area. It's like saying Perl is only useful for CGI scripts. While Lisp was certainly used a lot for AI work, it wasn't targeted at the AI field - it just happened to be the language best suited to it at the time.