Broadcasting classical information through a quantum channel

We consider transmission of classical information through a quantum channel from one sender to several receivers. In contrast to quantum information, classical information carried by two non-orthogonal states of a quantum system can be cloned exactly. This restricts a naive extrapolation of the standard no-cloning theorem. The optimal cloning induces entanglement between clones which increases with non-orthogonality of the states. The capacity of the corresponding quantum channel is considered. As a by product of our results, we obtain that for an entangled system with an unknown state there is no transformation a which removes the entanglement totally without affecting the corresponding marginal density matrices.