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In order to explain possible departures from the standard model ͑SM͒ predictions for bb and cc production at the Z peak, we propose the existence of a ZЈ vector boson with enhanced couplings to quarks. We first show that this proposal is perfectly consistent with the full set of LEP 1 and SLC results. In particular, Z-ZЈ mixing effects naturally explain the fact that ⌫ b and ⌫ c deviate from the SM in opposite directions. We then show that there is a predicted range for enhanced ZЈqq couplings which explains, for a precise and interesting range of ZЈ masses, the excess of dijet events seen at CDF. A ZЈ with such couplings and mass would produce clean observable effects in bb and in total hadronic production at LEP 2.