That error is cause by an improper notation in the "boot.ini" file which is created upon installation of Windows XP. Since this occurred during the installation phase, I suspect the version of Windows XP SP2 you're attempting to install is not compatible with Boot Camp.
You either need to use a genuine MS boxed full install of XP Home or Pro SP2, SP3, or an OEM System Builder's full install of XP Home or Pro SP2, SP3.
So called "corporate" copies or VL copies will not work. OEM specific copies such as from Dell, Sony, HP, Acer, etc, likewise do not work. Same goes for restore or recovery copies.
Regards.