Dualboot - Windows (Truecrypt) + Linux (LUKS) *

Split disk

Assuming this split of disk:

1. sda1 - >250MB Boot partition (unencrypted)
2. sda2 - partition for Windows (will be encrypted by truecrypt)
3. sda3 - Linux system partition (will be LUKS encrypted)
4. extended partition
5. sda5 - swap (will be LUKS encrypted)
6. sda6 - home (will be LUKS encrypted)
7. .... rest

Install Windows XP

Install windows to the second partition.

Install Linux + LUKS

During installation of the linux (assuming the Fedora), install grub to boot partition (sda1).
Do not bother with putting it to sda at this point as the next step would rewrite it anyway.

Next step is to install realcrypt (truecrypt package for Fedora)

sudo rpm -ivh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm
sudo rpm -ivh http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm
yum install realcrypt
Take backup of the bootsector - to use it in windows boot loader later on. Copy the file to some flash disk or other computer to have it handy when you will be in windows.

cd /boot
dd if=/dev/sda of=sda_grub.mbr bs=512 count=1

Install Truecrypt to Windows

This will reinstall the TrueCrypt to the master boot.
Copy the Grub master boot record to some direcotry in windows partition and configure the C:\boot.ini to be able to boot to grub from windows.
C:\BOOT\SDA_GRUB.MBR="Grub Master Boot"

Restore the Grub bootloader domination

Reboot the machine and use the Grub line in NTloader to boot GRUB
Backup the Windows/Truecrypt boot sector
dd if=/dev/sda of=/boot/grub/sda_truecrypt.mbr bs=512 count=1
Modify Grub - /boot/grub/grub.conf - option for Windows truecrypt
title Windows XP
rootnoverify (hd0,1)
chainloader (hd0,0)/grub/sda_truecrypt.mbr
Reinstall Grub to master boot (sda=hd0) and to the boot partition (sda1=hd0,0)
#grub
root (hd0,0)
setup (hd0,0)
setup (hd0)