Thnx for the replies, im a bit further now. I tried it with a new DVD, from iPC.

When i put my MAC drive as first bootable, i get the message "still waiting for boot device". When i put my WINDOWS drive as first bootable and select to boot Mac OSX, i get the Chain0 error. (I allready copied the Chain0 file to the root of my windows system).

My setup:

CoreI7 920
Gigabyte GA-EX58-UD4P
1HDD = Windows
2HDD = Mac
3HDD = Data

EDIT:

Im able to boot into Mac now and found my problem: I have 2 SATA disks in Raid0, 1 SATA disk for MAC and 1 SATA disk for data. To be able to boot into Windows, my bios was set to RAID, not AHCI. Now, i set this option to AHCI and im able to boot into Mac, but my raid disks are lost, so i cant boot into windows anymore. Is there a fix so i can use my Raid and also be able to boot into Mac without errors?