As far as I can follow matters, it has been known for about a year that perl-suid was going to disappear and consequently backuppc would not be able to run.

This now seems to have happened. If I try to upgrade Perl, Synaptic Package manager wants to remove backuppc.

People write things like "Easy, put it in a C wrapper!" which is Greek to me.

Question: Is there a way to carry on using backuppc in Debian Unstable or do I have to housebreak another network Backup program?

I don't have a problem to let Synaptic remove backuppc and then re-installing it outside of Synaptic.

Dude, perl-suid is alive and well; http://packages.debian.org/sid/perl-suid

You probably have installed some meta package/s.

You know what, I'm tired, but I found one link; http://wiki.debian.org/DebianEdu/HowTo/BackupPC

It might be helpful.

The problem is that my perl - and perl-suid - are v5.10. If I try to upgrade to the new release 5.12 then perl-suid will be uninstalled.

And there is where my problem lies. Perl-suid has been dropped from 5.12

A new version of backuppc, specifically to resolve this issue, is about to be posted to the repositories.

Good!