It looks like Apache is running your script under mod_perl. You can probably get around this by placing your script in the server's cgi-bin directory or perhaps just changing its extension to ".cgi". Looks like your Apache server is set up to treat any file with a .pl extension as a mod_perl file, which isn't a straightforward CGI script.

Update: As merlyn notes, the root cause is with the use of Link, but the reason that error seems obfuscated and the method of relaying the message is due to the fact that mod_perl (well, Apache::Registry) is taking over execution of the script. In all likelyhood, so long as caveats addressed in documents like http://perl.apache.org/dist/mod_perl_traps.html are observed, this script should still run OK.