Rotating A Child Bone

[TomorowsMemory]

I have a human rig and I have the arm with 4 bones one is the shoulder, bicep, forearm, and the hand. The shoulder is the parent bone and I want to make a helper that rotates the rest from the bicep down. The only problem is i can rotate the shoulder and the rest turn but i want to rotate from the bicep down and leave the shoulder bone. Why is it that the rest are locked and wont rotate? Here is a little diagram for those of you who might not get it. Each ">" is a joint inbetween each bone

Shoulder>Bicep>Forearm>Hand
[________________]

I want ^ (the underlined bones) to rotate and leave the shoulder alone. I want them to rotate on the X axis i think it is, or if you are in the front veiwport I want them to roll towards and away from the camera.

[neiy0]

show us more specifically what u want, why dont u just use a biped?