|I see this same problem yet I'm using the original XP CD from Dell that has SP3 on it already.|
I have OSX and Ubuntu booting fine, but the Windows boot starts up then stops with an "Unmountable BootVolume" error.
When I go to try to repair it from the recovery console it does not see drive C:. If I try to reinstall, it doesn't see any of the partitions on the SATA drive, just the whole drive with no partitions.
GPARTED sees all the partitions.
At the initial install of XP, XP saw all the partitions that were created in GPARTED and let me choose one for the install.
Both Windows and Ubuntu booted fine. It was the installation of OSX that screwed things up somehow.
After two weeks, I think I've come to the conclusion that you can't put Snow Leopard OSX, Windows XP, and Ubuntu onto the same hard disk. You can do it with Leopard, XP and Ubuntu, and you can do Snow Leopard OSX, Windows 7, and Ubuntu, but for some reason Snow Leopard doesn't like two additional OSes (XP plus Snow Leopard does work). Snow Leopard was modified to install on an MBR partitioned drive (an option that was always available on Leopard but for some reason was removed from Snow Leopard).