If the "normal driver repository" you are talking about is the GUI that you set up models and manufacturers, then that is gone. There is only one manager now and you point to the root of your driver directory and the manager will build a database and choose its own drivers based off hardware vendor IDs and DISM.
if you moved to SP3 unfortantly you are stuck with this method and cannot go back to the old GUI.
Here is more info:
Thanks for the reply. Which means I don`t have to even manage the driver library anymore? What I need to do is to copy and paste in the folder that`s all?
No, there is no need to import via the dialog (LD 9.0 SP3 obsoleted its usage) you only need to import your drivers into the driver folder, In a Dell shop, EXPAND.EXE your Enterprise CABs into the drivers folder and run the manager icon to detect/import the new drivers into the HII database.