As stated above, ensure that you're on 6.0.7.
While I've used this version on two different power macs, one with a Pioneer DVR-104, later upgraded to a Pioneer DVR-107D, on another tower I am using a Hitachi unit. Doubtful that you should be having a problem with whatever oprical drive you have in your portable.
I assume that you've completely rebooted - sometimes the internal drive electronics of the optical drive need to be reset - and this is the only was that I know how to do it - whether you use a desktop or a laptop.
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