To be able to join Windows 7 stations into a Samba controlled domain you must do the following steps:
- Make sure you have samba version 3.3.4
We also did try with 3.3.9 and 3.4.3 but have not been able to get it working in our environment....
- In the registry of the windows 7 system change these settings
You should now be able to join the domain and login as well.