How do I add PC BSD / FreeBSD to Grub 2 boot loader?

this is what I have in /etc/grub.d/40_custom. Works for me :) Just remember to subsitude hd0,3 with your correct entry

menuentry 'FreeBSD 8.0 64bit' --class os {
    set root='(hd0,3)'
    chainloader +1
}