please take a look at Debian Bug#589701: installation-reports: Install yaboot on a hard disk - Failed to install boot loader

[Rick Thomas]

At this point, Debian squeeze is un-installable on NewWorld PowerPC  
Macs due to yaboot's failure to adapt to the use of UUID= and LABEL=  
format in /etc/fstab.

	http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=589701

I have provided a partial fix in Debian bug#580455 but I have not  
gotten any feedback from the developers.

Rick