But you don't need to use Boot Camp Assistant, do you? AFAIK it only helps you to partition the HD and reboots the computer for you. Can't you just boot from the Windows disc by holding alt and then format or partition the drive through that?
Yeah, sorry for not being explicit about that. You can certainly do everything manually, as Mac Pro users (like hfg) have done for ever.
You can always install rEFIt if you want more control over the boot process than the standard boot loader allows for.
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