Ubuntu / Apple :: 10.04 Server On G4 Boot From Sonnet SATA PCI Card

I have a mac G4 Gigabit Ethernet, with 400MHz processor. I was running the Hardy version of Ubuntu Server last year, although I was booting from the onboard ATA controller. I just added a 2-port Sonnet SATA card and a single 250G SATA drive, and removed all the ATA gear. I installed 10.04 Server, and via guided partitioning wiped the 250G SATA drive, and installed yaboot. When I try to boot from the 250G SATA it hangs up at the "Mac Smiley <-> ?" Icon after the second stage bootstrap prompt, and then cycles.

I looked at some other threads, in fact read this about 4 times and got some good hints: [URL]. I can boot with a live 10.04 desktop CD, and mount the linux partition and look at yaboot.conf:
Code:
fdisk -l
/dev/sda
# type name length base ( size ) system
/dev/sda1 Apple_partition_map Apple 63 @ 1 ( 31.5k) Partition map
/dev/sda2 Apple_Bootstrap untitled 2048 @ 2048 ( 1.0M) NewWorld
bootblock .....

Then I did:
Code:
sudo mkdir /mnt/linux
mount /dev/sda3 /mnt/linux .....

I also tried to get some details on my PCI SATA card via "lspci". How to get this to boot? I haven't quite given up on this older G4 box. It will make a great SSH server and home automation box if I can just smoove out this wrinkle.