Yes, edit /etc/fstab. I hope you are using device names rather than uuid's, because that can be a pain in the arse.
With fstab, you can pretty much set the boot order and all, but mdadm (that is, software RAID) can be a serious problem if you like to sleep. Also, if you are striping, you can't recover.
I would install a real RAID card and not use software RAID, because it can really cost you, especially if you are striping. The uuid is the real problem. Even if you try to use "uuidgen" it isn't going to match.
I haven't tried it yet, but I have been thinking about skipping uuid and simply going the old way with ex. /dev/hda1 /, /dev/hda2 /var, etc.
I think that security has gone too far if I can't control my own farm, and I am in control of a lot of gig's.