Install Unstable package into Stable system? (was: Handling apt-get, apt-cdrom, sources.list, cdroms.list)

[Rodolfo Medina <rodolfo.medina@gmail.com>]

Hi.

I perchance need install the latest version of xpdf-reader,
the one included in unstable and testing repositories,
in my Sarge stable system.
This is not possible with simply `dpkg -i ...' because of dependence
problems.
In general: isn't it possible, it seems, to install an `unstable' package into 
a `stable' system without changing sources.list, i.e. without upsetting 
the `Stable' structure?

I'm new with Debian, excuse the basic question.

Thanks for any reply,
Rodolfo