Mavericks upgrade broke rEFIt/GRUB

I have a MacBookPro 5,3 runnning Ubuntu 12.04.5 LTS. I upgraded to OS X Mavericks a few days ago.

The OS X upgrade worked fine, and there were no visible changes to the rEFIT menu. However attempting to boot Ubuntu fails and I end up at the GRUB command line.
I upgraded to rEFInd and that menu boots correctly, however it produces the same problem, i.e. I end up at the GRUB command line.

I can boot into Ubuntu with the following commands from GRUB:
root=(hd0,3)
linux /boot/vmlinux-3.2.0-67-generic root=/dev/sda4 ro
initrd /boot/initrd.img-3.2.0-67-generic
boot

Evidently the problem is that rEFIT and rEFInd lost the correct settings.

I presume that the problem will be fixed by creating a suitable entry in refind.conf. Do any Mac users have sample entries for booting Ubuntu from a MacBook partition?

My grub version is GNU GRUB 0.97

Curious to see what other users are doing. Perhaps an upgrade to GRUB 2 or the use of newer EFI methods with rEFInd?

Thanks in advance.