Ubuntu - join client to AD
Make sure you can ping your DC by name (I simply added the searchdomain and nameserver to point at the DC)
Then install likewise
sudo aptitude install likewise-open5
sudo domainjoin-cli join HQ.SKYTECH.DK Administrator
Append to samba
cat /etc/samba/lwiauthd.conf winbind use default domain = yes
Reboot and login as "Other" and set username to be "<domainuser>@<domain>"