Download the pkges from berlios cairo repo, these:
Cairo-dock (http://prdownload.berlios.de/cairo-dock/cairo-dock_v1.6.3.1_i686.deb)
Plug-ins (http://prdownload.berlios.de/cairo-dock/cairo-dock-plug-ins_v1.6.3.1_i686.deb)
Themes (http://prdownload.berlios.de/cairo-dock/cairo-dock-themes-1.6.3.1.tar.bz2)
Copy/download them to ~/ or Home
Now lets install, run this in terminal
sudo dpkg -i cairo-dock_v1.6.3.1_i686.deb cairo-dock-plug-ins_v1.6.3.1_i686.deb
After that run this in terminal
tar xvjf cairo-dock-themes-1.6.3.1.tar.bz2
cd to pkg cairo-dock-themes-1.6.3.1
After that run: $./configure
Then run: $ make
Then: $ sudo make install
And finaly: $ make clean
Then run cairo-dock from menu.