The boot loader (r1934) runs on a iMac (Early 2006), except that it does not provide a menu interface and drops you to the command line. This was done with a blessed install on an HFS+ flash drive.
I also tried a MacbookPro2,2 (MBP22.00A5.B07) with the same result. However if I installed grub2 on a FAT32 partition on an internal HD, and used rEFIt to start that copy of grub2, I was able to get a normal looking menu.
I have been trying to get Ubuntu installed on my Macbook Pro's internal drive. However, the Macbook Pro's optical drive is not working, so I'm trying to boot live Ubuntu from a USB flash drive. The flash drive Ubuntu works fine on a BIOS PC, and can even start the iMac using rEFIt. But when I use rEFIt to try to start it on the Macbook Pro, it spews errors. I was hoping I would have more success with grub2... but when I run
the USB drive indicates disk activity for a few seconds and then stops, and the system is no longer responsive. Has anybody else been able to do something like this?
grub> appleloader USB
Hmm... some further testing and I was able to get the iMac to boot from the Ubuntu live USB flash drive after installing grub2 on the live flash drive, starting it via rEFIt, and using something like this:
Once again, this fails on the Macbook Pro. After the "boot" command the USB drive flashes sporadically but nothing else happens. Looks like MacbookPro2,2 may not be able to boot legacy systems over USB?
grub> search --set /casper/vmlinuz
grub> linux /casper/vmlinuz noprompt noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.gz
grub> initrd /casper/initrd.gz