[Samba] Problem: Smbpasswd allowing two users with the same SID

[Emidio Augusto Arantes Macedo]

When adding a new user using throw smbpasswd and the  SID  to be added 
already exists in tdbsam database, an error message is displayed like that:
hostname#  "( echo 'password'; echo 'password' ) | smbpasswd -as
'newuser'"
Unable to modify TDB passwd ! Error: Record exist
Unable to modify TDB passwd ! Error: Record exists
occured while storing the RID index (RID_00004a3c)
Failed to add entry for user newuser."

But when the same command  is runned again, the user is added with the 
same SID as the one already added, without any warnings. The SID 
calculated by the samba algorithm is based on the unix uid, but in my 
network uids are always being renewed. Does anybody had the same 
problem? Is there anyway to always block smbpasswd when adding a new 
user with an existing SID? Thanks! Using samba 3.14a

Emidio