building packages from hardy source for gutsy

[Donatas G.]

The way I usually do it is this:

add the deb-src for hardy to /etc/apt/sources.list
do 
	apt-get update
then do 
	apt-get source kdesudo
which would set up the sources for me. 

And then - the usual 

cd kdesudo 
sudo apt-get build-dep kdesudo
dpkg-buildpackage -rfakeroot -uc -b
cd ../
sudo dpkg -i kdesudo*.deb

However, I have seen in some howto the manual way of doing this - so that I 
would not have to apt-get source the package (and change the sources 
repositories to hardy if I still need gutsy once in a while).

What is the command to execute that sets up the sources, once I have 
downloaded the appropriate
	kdesudo*.tar.gz
	kdesudo*.diff.gz
	kdesudo*.dsc 
files?

I do also remember (from the old time I used debian) that apt is capable of 
using the specified release version of the packages to download (or install) 
using the -t releaseversion option. But I have to set up apt-get to do that 
as well as adding the proper repositories. This would be even more convenient 
than the above thing, does anyone know how to do that in Ubuntu?

-- 
Donatas Glodenis
http://dg.lapas.info