This is an old post so my answer is just for future searches.
If you want to run a pure Perl environment you can separately install the latest version of Perl with PerlBrew. (google it). This will set the latest Perl in your home folder, separate from the one that comes with OSX.
Several good reasons for this...
OSX's Perl tends to be downlevel - this way you can get the latest.
The new install will be stand alone, and will not require any interaction with system files, so you don't run the risk of nuking your system by making system wide changes during install or updates.
Installing addons like Perl/TK and pkdev and all the CPAN modules you want becomes dead easy, with no worry about missing or wrong libraries. Again, without the risk of whacking your OS.
And, if you should mess up your private Perl environment, just delete the whole Perl folder, then install it again.
When you do a Cat upgrade, say from Lion to Mountain Lion, or from ML to Puddy Tat (or whatever comes next) any changes to the system Perl are destroyed, including that weird CPAN module that you need, but can't for the life of you remember how to install on OSX. WIth PerlBrew, it doesn't care if the Cat has spots or stripes - it just keeps working.
For heavy Perl users, especially those who move scripts back and forth between OSX and 'nix boxes, it takes a lot of the hassle out of maintenance.