Newbie w/a Mac: Q. on burning a boot cd

[rainstorm]

I'm trying to burn a boot cd for my dreamcast.
I've downloaded several different .cdi files to try out.
(dc hakker, utopia...)
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I'm running a Mac, so I don't have any special burning programs, just the one that came w/the computer.
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When I burnt the cd using the regular brun option my dreamcast treated it as a music cd.
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any help would be appreciated. Ty!

[terminator]

google for "discjuggler mac"