At least on my webserver with cPanel installation of perl modules, the documentation for installing perl modules (not sure if it's cPanel or ISP documentation) lists a 'use' statement that will set up the use-lib properly for where cPanel installs the modules. Let me go look it up:

Your Perl script needs instructions to find the modules in your path.

To do this, add one of the two choices below to the top of your script:

#!/usr/bin/perl
use cPanelUserConfig;
[download]

- or -

#!/usr/bin/perlml
[download]

So, at least on my server, if I use the perlml version, it doesn't need the special include, but you might want to try the use cPanelUesrConfig; anyway (it may be that perlml is different on your cPanel than on mine).