> This is interesting, because on MY mac mini under system profiler it reads:
>
> Matshita DVD-R UJ-845C:
> Firmware Revision: 			DPP9
...
> DVD-Write:					-R, -RW, +R, +RW

Yes, the firmware version on mine is different:
Firmware Revision:	D8PB

I suspect that if you get a firmware updater, you'll be able to do dual 
layer, too.

John