All was fine on my development box, the trouble began when I started to test the application on our production environment. I'd forgotten that this application lives on a box running with the OS installed Perl 5.6.0.
"No problem compile 5.8.x" you might say. We aren't allowed compilers in production, and I have no test box matching this configuration. "Install a binary", I managed to find one that was approved for use. The application requires XML::Parser (requiring a compiler). Tracked someone down with a compiler, right version of Perl, wrong compiler.
Back to trying to use 5.6.0. We have a local CPAN::Mini::Inject mirror that we use for our other applications, so this was a natural choice of where to install modules from (plus the application server does not have Internet access). Configured CPAN, try to point it at our local mirror. No luck. We use HTTP access (ftp not being allowed) and LWP had never been installed on this server (no wget, nor ncftp either).
Copy LWP over by hand, discover it's prerequisites, and do the same for each of those. I'm now stopped by not having a compiler and not having Perl 5.8.x to install an LWP prerequisite.
I've found someone to compile Perl and the modules that require compiling for me. Hopefully I'll be able to use CPANPLUS to install the rest of the modules and move on.