For users of the Debian Sarge also called Debian Stable :
Glibc
I finally got it working :
I had to upgrade my glibc
name of the package : libc6
The package of the Sarge is too old for Plainshift
The package of the testing is ok. It is stable already, so it shouldn\'t hurt to install it.
How to do (as root) :
1) make a backup copy of your /etc/apt/sources.list
2) edit your /etc/apt/sources.list
3) replace stable and sarge by testing
5) type in a shell where you are root :
apt-get update
apt-get install libc6
6) you should have only 2 or 3 packages upgraded : if it\'s not the case, send me a PM to ask for help
7) IMPORTANT : restore you backup copy of /etc/apt/sources.list

check that there IS NOT the word testing in /etc/apt/sources.list
now you should be able to run plainshift under your debian stable
note : upgrading your libc is a hazardous operation that may damage your system : make sur you have a gentoo, or any other CD-Bootable distribution in case of damaged system.
note2 : if the apt-get update commande fails, try a /etc/apt/sources.list with only this line :
deb
http://ftp://ftp2.fr.debian.org/debian testing main