Cannot enable DMA od DVD burner under 2.6.12

[Žáček Kryštof <Krystof.Zacek@i.cz>]

I have SATA disk on /dev/sda and IDE DVD burner (LG) on /dev/hda. The chipset is Intel 82801EB.
I fought hard to install Debian on this machine with debian-installer's linux26 (atapi-piix SATA driver is crap in 2.6).

Now DVD works and I would like to enable DMA on the IDE /dev/hda burner but hdparm gives:

hdparm  -d1 /dev/hda

/dev/hda:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 using_dma    =  0 (off)

I am using the stock debian kernel 2.6.12-1-686 and up-to-date unstable system.

Any help would be appreciated.

Thanks,

Krystof