How to read forces ?

[NewbTon]

In case a jointed model (ragdoll) punches another ragdoll I'd like to know the accumulated forces
at the point of contact. But when I call the getForce() or getTorque() on the bodies they return [0,0,0].
When I  use   jointFeedback I can get something but is it the right result ?
I would imagine that jointFeedback only returns the force being applied to this joint and not the accumulated forces..