You didn't break it - Apple did. See http://bulknews.typepad.com/blog/2009/02/mac-os-x-security-update-2009001-breaks-perl-cpan.html - Apple brought back bad versions of some of the XS code (for IO, Scalar::Util, and Storable).

You'll need to hand-download and install those modules over again to fix it - download from CPAN, untar, cd in, perl Makefile.PL, make, make test, sudo make install for all three.

Other notes: never replace the system binary Perl - system updates may undo your work at any time. Always build your own somewhere else; if you use MacPorts, it will build in /opt/local for you.