Running on Debian Etch I had to upgrade the NUT package but this
worked very simply by bringing in the one from Lenny (in testing)

added to /etc/apt/sources.list
deb-src http://ftp.uk.debian.org/debian/ lenny main contrib non-free

then ran
apt-get build-dep nut

as normal user
apt-get source nut
cd to nut dir
dpkg-buildpackage -rfakeroot -uc -b

then as root installed the .deb created

After that it was just a case of reading the docs and configuring.

I’m using the UPS for my desktop and monitor - it’s drawing 25% load
with a predicted battery runtime of about 45minutes (which I don’t
quite believe)