I tested it completely.
Dvd burning worked right after installation, yes with roxio toast 9. I installed no chipset kexts (sb600 for my board) during installation so drives in bios were set to sata->ahci mode. Toast works fine, no errors or whatsoever.

Later i installed chipset kexts, booted in native ide mode. This way i cant burn, 0x20 illegal request (or something like that). So if i want to burn i have to set drives to sata->ahci and then burn with toast.

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