bit and Windows xp 64 bit?
I've tried that already ( both operating systems are installed error occurs when trying to boot to windows xp 32 bit) but I get an error:
windows could not start because the following file is missing or corrupt:
<windows root>\system32\ntoskrnl.exe.

Same as any dual installation, format the drive, partition it, load your operating systems

support.microsoft.com/kb/313348