Update. Just spoke with Per on msn (the one with the problem with OSX 10.4.9) and learned the following :
1. His problem was not fully described in his posts. He has no internal duallayer on his MBP, so he bought an external LiteOn burner.
2. This liteon burner worked perfectly in 10.4.7 on his MBP.
3. When he upgraded to 10.4.9, it failed to work (same growisofs error as I have).
I always assumed he was talking about his internal burner, and you guys probably also thought this. But it turns out, this error is not a 'fluke' as appleguru stated a few posts back.
So, I dare anyone, with an EXTERNAL burner AND OSX 10.4.9 to try and run growisofs. If it works, please state the type of external burner, your machine and the type of media you are using.
If it doesn't work, there is something fundamentally different in 10.4.9 <> older version which prohibits external burner + 10.4.9 + growisofs to work.
Lam47.. you go first.. 10.4.9 ? External burner ?

Well, something to try is to load the old (10.4.
kexts in place of the new ones...
10.4.9 came out on 3/13/07.. based on that it looks like they updated the following kexts:
The system, firewall, and graphics ones are probablly pretty harmless here.. That leaves IOPCIFamily
(NOTE: Not for newbs... you need proper permissions and you need to properly kextload the kernel extension for it to work. Failure to do so could lead to an unbootable system!)