Samba4 'The account is not authorized to log in from this station' attempting to join domain

[steve]

On 05/05/12 11:49, steve wrote:
> Hi
> alpha21-GIT-027f2b3
>
> We can no longer join machines to the domain.

Looks like it's Samba4 :-(

We can join the xp and win7 clients to another test domain no problem.

Why should I get that msg. with that istall?
Cheers,
Steve