samba - Jul 2010 - How to define an UID range for BUILTIN accounts

Hi all,

I've got a Debian Lenny Samba server on which I'm trying to define UID  
ranges for the handful of domains it connects to.
I'm using the RID backend successfully for the domains: I can switch  
to it successfully from the old self defined UID's, and then getent  
passwd/group show the new expected ones.

However, the BUILTIN accounts also seen getent passwd don't change.  
I've been trying to define them in the same way as the domains, and  
some other things I've googled, but nothing. With most of my tries,  
after removing the Samba cache and tdb files, the BUILTIN accounts  
simply disappear and don't come back.

Any idea or pointer on how to define those BUILTIN UID's successfully?

TIA,

Laurent