Just an update. I've download the distro "SNOWLEO MAC Snow Leopard OSX86_64 For INTEL/AMD 32/64 MBR/GUID" and it almost worked. Managed to boot on installation disk but still trying to figure out combination of kernel/patches that will work on this hardware.
The closest I got was using Chameleon RC4 PC-EFI 10.5 (asereBLN) for booting, pcj kernel, amd patch, ApplePXIIATA and acpi kernel panic patch. In the end I got a time out for AppleIntelACPI something, which I dont really know why it happens.
I'd suggest you to give it a try and let me know how it went.