XDMCP login remoto

cp /usr/share/doc/gdm/examples/custom.conf /etc/gdm/

# GDM configuration storage

[xdmcp]
Enable=true
DisplaysPerHost=2

[chooser]

[security]

[debug]

 /etc/init.d/gdm restart

 apt-get install remmina remmina-plugin-xdmcp

http://www.peppertop.com/blog/?p=690

http://www.informatica.escuelaedib.com/wp/2010/10/servidor-x11vnc-de-escritorios-remotos-disponible-en-el-arranque-de-ubuntu-maverick/