Troubles with Dual boot Vista and XP Home

Hello,
Ok, here is my issue. I purchased a PC for a friend and it has Vista already installed. Well, I am trying to set up a dual boot system but here is the thing. I know dual boot on the same partition is easy but what I am trying to do is set up XP Home on a separate 320G hard drive (keep in mind, these are both SATA drives). The PC recognizes both drives in Disk Management but when I try to reboot with the XP CD installed, it starts to load the files in the XP blue screen and then after it completes, instead of asking me to install XP it goes into a separate blue error screen saying I should check the hard drive for viruses, and to check the config of the physical drives? SO, I cannot install XP on this separate SATA drive which does not require jumper configuration. Under disk management Vista is installed on C: as it should be and I mapped the secondary drive J: -Under BIOS, it only shows one SATA drive controller and not the second. What am I missing here? Any gurus out there want to help? Thank you much.

Pete