not an answer but are you aware of XP dual boot issues that may affect you?
1) What exactly did you format your sata as....eg cfdisk /dev/sda or fdisk /dev/hda or hde? etc
2) are you aware that the kernel in ramdisk you used to install your distro is not necessarily the one that is trying to boot up your HD?
which means you may have a booting kernel which has not got the correct sata supports in them.
this is a known issue but the new kernel 2.6.8 ( I don't have 2.6.9) mentions that you no longer use normal scsi but scsi subsystems in the compile process and you should find a promise subset to enable in the kernel rather than a module.
I am not a kernel expert, not even a grub expert, as I have no sata, but I suggest its the kernel not grub you may care to check out and eliminate first please???
3) you could also try some kernel append lines like
ide=reverse (to search scsi b4 ide)