Abstract
The indirect exchange interaction between two localised magnetic moments is calculated for Hg1-xMnxTe alloys near the zero-gap semiconductor transition. For such Mn concentrations the non-parabolic effects are overwhelming and have been accounted for properly. The electron-heavy-hole virtual transitions are shown to be larger than the electron-light-hole transitions. The net exchange integral is antiferromagnetic; the numerical value of the Curie-Weiss temperature is calculated and compared with experimental determinations.