How are you transferring stuff to the embedded system? Can't you just do something like: (scp to the box)
No. Remember the system boots from a filesystem image. It's created beforehand and installed on many, many units in production, and, thanks to the fact that it's in RAM, FS changes are destroyed on every reboot (and that's a good thing).
Or build a perl5.8.8 on your build system, which has the same @INC as the one on the embedded system, and use that to build your modules. Then you can deal with non-pure Perl modules as well.
I also mentioned that the host and target architectures differ, so this wouldn't gain anything. However, I'm really only worried about pure Perl modules. ikegami hit the solution on the head, though, so fortunately nothing like this is necessary, which is what I'd hoped.