  In this article, we generalize Loday and Pirashvili's [10] computation of the
Ext-category of Leibniz bimodules for a simple Lie algebra to the case of a
simple (non Lie) Leibniz algebra. Most of the arguments generalize easily,
while the main new ingredient is the Feldvoss-Wagemann's cohomology vanishing
theorem for semi-simple Leibniz algebras.
