I'm not sure what you are trying to do, there is RAID how-to in Chameleon's docs I think, but I think you need to put the boot-uuid value of the RAID volume in chameleon's boot arguments, you can see it in Disk Utility, open properties for the array.
Also pressing TAB while in Chameleon menu will switch to text mode and you can see the disk identifiers next the each menu entry.

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AsRock P45TS | C2D E8200 | GeForce 8600GTS
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