  It is investigated whether canonical suppression associated with the exact
conservation of an U(1)-charge can be reproduced correctly by current transport
models. Therefore a pion-gas having a volume-limited cross section for kaon
production and annihilation is simulated within two different transport
prescriptions for realizing the inelastic collisions. It is found that both
models can indeed dynamically account for the canonical suppression in the
yields of rare strange particles.
