That's easy :)

You have to configure your server to use index.pl or index.cgi (or whatever you want) as a default Index page. If you are using Apache web server, then you have to use DirectoryIndex directive. Here is a an example from my config (/etc/httpd/conf/httpd.conf):

#
# DirectoryIndex: Name of the file or files to use as a pre-written HT
+ML
# directory index.  Separate multiple entries with spaces.
#
<IfModule mod_dir.c>
    DirectoryIndex index.epl index.html index.htm ndex.shtml index.php
+ index.php4 index.php3 index.phtml index.cgi index.epl index.pl index
+.mhtml index.mpl
</IfModule>
[download]

It is possible in any(?) other server too. I've seen it even in MS IIS, but don't remember where. :)

Leonid Mamtchenkov