question about DTSHD-MA 4.0

[sowecrazy]

one of my blurays has that codec and i have a 7.1 set up, sound and score come out of the right and left fronts, diolouge out of the center and bass out of the sub, thats 4 channels. no sound comes out of the surrounds which i understand, but sound comes out of the rear surrounds the back speakers aka 6 and 7th speaker, i'm wondering why it out-puts this way. was it just mislabled?, i do have my set-up correctly hooked up and i'm useing a ps3 so thats decodeing the sound.