After having August's worth of perl5 related archived messages for
tech-pkg, I'll chime in:

As has already been mentioned, the updating of the perl5 package itself
from one version to another is a rather complex issue because all the
packages depending on perl5 needs to be revisited. In the case of binary
package distributions I really don't know how to handle this.

As a user who for various reasons has experimented with several release
and pre-release perl versions and consider perl5.004_04 rather old, I'll
raise the following idea which has almost been mentioned on this mailing list:

In bsd.pkg.mk, change the USE_PERL5 section to something like

.if defined(USE_PERL5)
PERL5_DEPENDS?=         perl-5.00404:${PKGSRCDIR}/lang/perl5
DEPENDS+=               ${PERL5_DEPENDS}
.endif

What happens here is that the use gets a chance to set PERL5_DEPENDS in
/etc/mk.conf, possibly to select between several perl5 packages in a
transition period. You may even set it to some non-pkg version of perl,
which will cause perl-installed files to end up in places where pkg_delete
will not expect them, but the running package should still be ok. When
doing this, you'll of course take the full responsibility of installing
and/or upgrading all the necessary p5-packages.
Doing this may be more sound that allowing perl-5.00(40[45]|503) as the
person setting mk.conf selects exactly one perl5 to use and we have a chance
to reinstall all packages depending on perl5.




Another issue: Sometimes a package just needs a perl while building itself,
but no files will be installed within perl itself. Maybe USE_PERL5 should
be divided into two variables, one that just requires a perl5 while building
the package, the other one requiring an actual perl5 package because files
are installed into /usr/pkg/lib/perl5/...


These two issues seem to be orthogonal, and one and/or the other could be
considered in any sequence.

regards
Erik Bertelsen