The electronic states of stressed heterojunctions formed from narrow-gap semimagnetic semiconductors showing antiferromagnetic ordering are studied. The model Hamiltonian is constructed in the framework of the two-band envelope-function approximation including far-band corrections. Heterojunctions, both with normal and inverted band arrangements in the initial semiconductors, are investigated. The interface Tamm-like states have been shown recently to appear in these heterojunctions, and they are spin split with the magnetic axis perpendicular to the interface plane. The effect of far-band corrections is shown to be conditioned by the mutual movement of the constituent bands, resulting in changes and in some cases in the full disappearance of the energy interval in which the interface state exists. The interface magnetization effect is expected when the Fermi level lies in one of the spin-polarized interface bands. Using the appropriate parameters, the value of the relative interface magnetization is calculated.