Technically no, they're made now so that that is impossible. They actually physically will not boot into OS 9. Which is fine by me, I only booted into it once, and that was to set it up. I don't even have Classic installed anymore.
No need to go that far. If it's that important for you to boot into os9 (which is very confusing to me, since classic works just fine), you might want to search for firmware hacks. I heard there are some available
