SUSY-QCD corrections to MSSM Higgs boson production via gluon fusion

In the MSSM scalar h,H production is mediated by heavy quark and squark loops. The higher order QCD corrections have been obtained some time ago and turned out to be large. The full SUSY QCD corrections have been obained recently including the full mass dependence of the loop particles. We describe our calculation and present first numerical results. We also address the question of the proper treatment of the large gluino mass limit, i.e. the consistent decoupling of heavy gluino effects, and present the effective Lagrangian for decoupled gluinos.