the memory limitation

I am new with breve and I am trying to have a 3d simulation of a population of cells which migrate, proliferate(create daughter cells), and dye based on random walk. I need contact inhibition between cells as two cells may not occupy the same position but it the number of cells (agents) increases dramatically and the computer runs out of memory, is there any way to be able to use more than 4GB of ram with breve as apparently its a 32 bit application?
Thanks