Few GRBs clearly present distinct High-Energy (HE) component that evolve independent of
the usual Band function that describes the prompt keV-emission. This component can be long
or short lasting compared to the burst duration. However, most of models only explain the
long duration HE component. We have developed a leptonic model on the external shock
framework to describe the HE components. We propose that the short HE component that falls
in the MeV regime in coincidence with the prompt phase and, the second long lasting
GeV-emission could be understood as synchrotron self-Compton (SSC) emission from the
reverse and forward shock respectively. This model requires a magnetized jet and a reverse
shock in the thick shell case. This model already has been proven in GRB 980923 and GRB
090926A, the former with a short duration MeV-component and the latter with both long GeV-
and short MeV- HE components. All fluxes, energies and durations are consistent with the
observed values. Here, we apply this model to GRB 940217 that presented similarities with
GRB 090926A and GRB 980923.