Linux PPC Live-CD not booting: why?

[Luca Manganelli]

Hi, I'm a totaly newbie with PPC systmes (my friend has an old iMac G4
733 Mhz - the mac that fits all into a roundet and transparent
blue-white CRT monitor).
I have recorded a CD with live version of ubuntu and gave it to my
friend. My friend inserted into CD, then rebooted its Mac OS X and
none happened: boots only to Mac OS X. Pheraps there's a command to
boot to CD and not to HD?

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"An algorithm must be seen to be believed."
   -- Donald Knuth, in "Fundamental Algorithms"
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