mod_perl may not be what you are looking for. Is the perl script designed to be run with mod_perl or is it a cgi script?
First, lets consider that it is a cgi script and not really meant to be run as mod_perl. If that was the case, in your block of your config, you could put:
<Directory /path/to/webroot/>
Options +ExecCGI
AddHandler cgi-script .pl
</Directory>
If the script had a proper #!/usr/bin/perl line at the top, and was able to be executed, apache should then serve it as a CGI script.
However, if you really do want to use mod_perl, you generally need to write a handler inside your VirtualHost config like:
<Location /virtualpath>
SetHandler modperl
PerlResponseHandler modulename::Function
</Location>
you might also need to put:
PerlRequire /path/to/startupscript.pl
to do your environment fixups. Generally, mod_perl handlers are .pm files and are packages rather than .pl files.