Mac has a very easy way to change your perl @INC path.
Just append the required directory to the file
/Library/Perl/5.8.8/AppendToPath

Note the version above (5.8.8) may differ for you. To find out your perl version,
type perl -v in the terminal.

listsettle-lm:~ anshup$ perl -v

This is perl, v5.8.8 built for darwin-thread-multi-2level
(with 4 registered patches, see perl -V for more detail)