wrong UID from open directory server

I have a problem with a mac OSX server

I have an open directory server A, that shares all users to every other server i have.

I then have 2 mac OSX servers B and C, that it set up to allow network users. I can easily login with a open directory user, on both servers, but I have a problem. on server B it says the users user id is 1050, which is correct. On server C it says that the same users user id is 1000, which is wrong. Both server set ups are identical, as far as I know. On the Open Directory server A the users id for the user is also 1050, in case that is relevant.

I have checked if server C has a local user with the same name, but htat is not the case.

Any idea what might have caused this problem?