Global user registration only?

Hi

Is allowing user registration a global only setting or can you set individual blogs to allow or not? e.g. one blog having no user registration while another allows it.

I can see where the global setting is and it’s working and I can see where the individual blogs can set the 0/1 switch but it seems the global setting overrides this – all blogs have user registration or all don’t.

How can I make the individual blogs be set differently?

Cheers