Pinning; w: Didn't understand pin type

[Saviour Of All Soulz <saviour@soulz.wox.org>]

Hi everybody, i've been trying to get this pinning working.
I've got Woody installed and I want to be able to get packages from Sid.
So I got the tip to try out pinning.

I get an error though, everytime I want to install a package:

===================
W: Did not understand pin type  release a=testing
===================

This is'nt very convenient beacause now I can't do an apt-get dist-upgrade, 
that will install Sid, wich I don't want.

This is my /etc/apt/preferences file:

===================
PPackage: *
Pin: release a=testing
Pin-Priority: 101
===================

This mis my sources.list:

===================
## Woody

deb http://security.debian.org stable/updates main contrib non-free
deb http://ftp.debian.nl/debian woody main contrib non-free
deb http://ftp.debian.nl/debian-non-US woody/non-US main contrib non-free
deb-src http://ftp.debian.nl/debian woody main contrib non-free
deb-src http://ftp.debian.nl/debian-non-US woody/non-US main contrib non-free
deb-src http://non-us.debian.org/debian-non-US woody/non-US main contrib 
non-free

# Sid

deb http://ftp.debian.nl/debian unstable main contrib non-free
deb http://ftp.debian.nl/debian-non-US unstable/non-US main contrib non-free
deb-src http://ftp.debian.nl/debian unstable main contrib non-free
deb-src http://ftp.debian.nl/debian-non-US unstable/non-US main contrib 
non-freedeb-src http://non-us.debian.org/debian-non-US unstable/non-US main 
contrib nonfree
======================

What am I doing wrong?

Tnx in advance