Most likely, your upgrade of Macports left behind installed modules with the old version of Perl. You will need to reinstall all modules that got left behind. Maybe the Macports (whatever that is) also offers packaged Perl modules?

Your secondary error seems to be somehow related to permissions of the directory /users/UserName/.cpan or something below it. You don't show the permissions, so I can only guess, but you will need to give the user running perl -MCPAN -e 'shell' the appropriate permissions for the directory.