configure Boot with 2 hard drives

[Luigi]

Hi everyone,

I've got two hard drives on my pc:

Master /dev/hda1,hda2,hda3

and

slave /dev/hdb where I've installed PC-BSD.

I want to configure a grub who propose me to boot on my first drive of 
my second drive.

Is it possible? How can I do it?

Thanks for your answers.

Luigi