I found this on the FreeBSD mailing lists. Awfully helpful.
i) Install the perl5.8 port:
> portupgrade lang/perl5.8
ii) Set the new version of perl to be the default.
> use.perl port
iii) Re-install any 3rd party modules
> find /usr/local/lib/perl5/{site_perl/5.005,5.00503} -type f -print0 | \
xargs -0 -n 1 pkg_which | sort -u > /tmp/perl-ports
> portupgrade -f `cat /tmp/perl-ports`
Many thanks on documenting the procedure in a nice short way.
