  We show that new physics, either from CPT violation in B^0-\bar{B}^0 mixing
or from \Delta B = -\Delta Q transitions, may lead to an opposite-sign dilepton
asymmetry of neutral B-meson decays. Both effects have the same time-dependent
behavior and therefore are in general indistinguishable from each other. We
also clarify some ambiguity associated with the constraint on CPT violation in
semileptonic decays of incoherent B^0 and \bar{B}^0 mesons.
