pl/perl and recent perl versions - failing to load internal modules

Hi,
I've been trying out PostgreSQL 9.3 with pl/perl built against Ubuntu 14.04 LTS' Perl 5.18
(Sourced from apt.postgresql.org)

Maybe I'm doing something wrong, but it appears that plperl has become completely useless, as it can't load any new modules, but modern Perl versions have refactored the language into lots of small modules that are automatically loaded as required. Except they can't be loaded as required.

For instance, a fairly simple regex will try to load the modules: utf8, utf8_heavy & re
Since it is forbidden from loading anything, it will fail.

You can still use the unrestricted Perl module, plperlu, but this requires superuser permissions to use, and in the past its use has been discouraged.

I've experimented with using the plperl.on_init configuration option to try and include all required modules, but this requires trial-and-error and can easily cause new failures to appear if a stored procedure is changed a little.

Has anyone else encountered this? Am I doing something completely wrong?

Thanks,
Toby