Beware - I have no experience on Activestate, but I do have some experience with Apache and Perl on Linux. If you can locate your Apache configuration file(mine on Red Hat Linux is /etc/httpd/conf/httpd.conf), look for something like this

  #AddHandler cgi-script .cgi
[download]

and uncomment it. Then save the file, and restart Apache, and try browsing to you script.

That will allow it to recognize scripts with a .cgi extension - I'm not sure what you need to do to get it to run .pl extension scripts, but just to see if it works rename your .pl file to .cgi. Might be as simple is either adding a '.pl' to the AddHandler line above, but I really don't know.

HTH.