I am 99% certain that this is no longer a 'problem' for the current bindings available from Sourceforge. (However, the discussion seems to indicate that we need to update the bindings so that a single stream can be set to a different filename.) Of course, the PLplot bindings for Perl are not in their own Sourceforge project, so you'd never find them. :)
You can git them with this command:
git clone git://pdl.git.sourceforge.net/gitroot/pdl/pdl-graphics-plplot
Build instructions follow the standard incantation and are documented near the end of the README, which you can read without needing to download here:
You can also browse the repository here:
Hope that helps!