  It is shown that Smolin four-qubit bound entangled states [Phys. Rev. A, 63
032306 (2001)] can maximally violate two-setting Bell inequality similar to
standard CHSH inequality. Surprisingly this entanglement does not allow for
secure key distillation, so neither entanglement nor violation of Bell
inequalities implies quantum security. It is also pointed out how that kind of
bound entanglement can be useful in reducing communication complexity.
