[Joe826]

Nice thoughts. Your analysis would be accurate if God were just any other guy, like you or me. However, the orthodox belief is that God is the creator/inventor of all things and so he assigns to them an order of his choosing. If this is the case then thou shalt not murder is just as objectively true as 2 + 2 = 4. If God exists as christians portray him, then he defines all relations -- logical and otherwise.

In answer to the actual question, the answer most certainly has to be yes. Kant proved nothing, since his catagorical imperative was still based on notions which could ultimately be viewed as subjective. In order to have an objective moral system, there has to be an objective standard by which to judge rules.