Since the wall you're framing isn't a load-bearing wall, you need to simply frame out a header. Obviously, the header needs to run the length of the door and the pocket (and then some in the pocket.) If you can frame a header, you should be all set. I say this because, again obviously, you don't stud-out the pocket. Sooooo, you have to ask yourself, "How do I frame a wall w/o studs?!"