How to enable to install backports packages
You have to edit the file :
and add a line in the file. It will tell to apt-get where to get the backports packages, so, add this line :
deb http://www.backports.org/debian etch-backports main contrib non-free
Then, you have to run :
# apt-get update
and now, you are able to get a package from backports, but by default, if you won't say something, apt-get will install you a "normal" package, that doesn't come from a backports packages. So, you have have to tell apt-get that is a backports package, like this :
# apt-get -t etch-backports install WANTED_PACKAGE
and replace :
by the package that you want.
That's it, you can, by instance, install the newest kernel available from debian team. Enjoy it !! You can find more information on this page if you want.