I think I found the procedure from an old post, I hope it's correct. Thanks.
Now this is a big assumption that the '09 is the same as my '06, but in the '06 there is a small hole in the rear rotor (accessible by taking off the rear wheels) covered by a small round black rubber grommet thingy. Jack up both rear wheels with car in neutral and parking brake OFF. CHOCK BOTH FRONT WHEELS SO CAR WONT ROLL!!!! Remove wheels. Doing one side at a time find the small rubber grommet hole and pop out rubber cover. Turn wheel by hand until the hole is directly on the bottom (6 o'clock) use a flash light to peer inside, locate a little round thingy with teeth on it and use a regular (flat) screwdriver to to turn it. I forget which way but it may be up to tighten. Turn till its snug but u can still turn wheel by hand. Repeat for other side. That should do it.
EDIT: you can also adjust the cable under the dash. it is connected to the foot brake pedal. i just tightened mine up and its much better now.
It is not self-adjusting according to the FSM. Nate is correct. The cable adjustment nut is located at the pedal. The procedure is first to set the brake shoe clearance, through the access holes in the rotors, then adjust the cable so that the brake sets firmly after 5 to 7 clicks.
PS I doubt the OP or #5 are still around.