First of all, thanks a lot to Liggy for developing necflash. It has dumped the firmware (1AHM) of my Optiarc AD-5630A DVD drive and flashed Liggy's RPC1-version without problems under MacOSX.
However, necflash does not seem to be able to change the DVD+R-DL's book type:
$ necflash -querybt A:
Binflash - NEC version - (C) by Liggy and Herrie
Currently no disc is inserted
Permanent booktype for DVD+R is DVD-ROM
Permanent booktype for DVD+RW is DVD-ROM
The permanent booktype on DVD+R-DL cannot be changed
I, of course, haven't managed to change the book type to DVD-ROM (neither Temp nor Perm booktype arguments worked). I have also looked for a booktype firmware modification to no avail.
My question to Liggy is, Is this a physical limitation on the drive which makes setting the DL book type impossible through a firmware modification?