[MacDV] firmware upgrade for G4 400 DVD writer

[animal]

Hi

I'm looking to upgrade an old G4 400 sawtooth to 10.2 and a DVD writer. 
  Due to an old scanner I have to be able to still operate this machine 
in OS9.

Both the Pioneer 105 and 106 DVD writers are compatible with this model 
- but does anyone know if I have to upgrade firmware also?  I'm 
concerned that the firmware upgrade will prevent me from using OS9.

Thanks
Lynn