I'm just thinking through the implications of this... General relativity says that mass and energy are equivalent; an electron produces as much gravitational at

I'm just thinking through the implications of this... General relativity says that mass and energy are equivalent; an electron produces as much gravitational attraction in another particle as an equivalent amount of energy does. If matter and antimatter gravitationally repulse each other, then an electron and positron in close proximity will produce a near-zero amount of acceleration in a nearby particle, since the attraction and repulsion cancel. However, if they annihilate, producing gamma rays, then the gravitational acceleration experienced by that nearby particle will suddenly increase, since the energy of both particles will occupy the region previously occupied by the matter and antimatter. Is that correct? That sounds wrong. Why should the net gravitational "charge" of the gamma rays not be negative or zero?