Very strange. You should have seen Grub then..
It could still be that the bootloader is in hda while the rest of Windows is in sda (I think).
What should work though if you follow the "Setting Up the Bootloader for RAID" in
FakeRaidHowto, running the grub commands and setup to your
hdb drive. I presume you haven't actually got RAID set up with one of those strange /dev/mapper/ devices though (?). The Grub commands should broadly be the same though if you manage to work out the correct names for your drives accoridng to Grub.
You then run this: dd if=/dev/hdb of=/mnt/floppy/linux.bin bs=512 count=1
You need a floppy to write to. The file linux.bin can then be copied onto your C drive in Windows. You then have to add Linux to your windows boot by editing boot.ini.
You can also try to install grub to hda, and see what happens. Maybe best if you have a bootable Windows DVD, so you can run fixmbr from the DVD repair console if something goes wrong.