The microscopic phase space approach RQMD1 is used to investigate the
stopping power of very heavy nuclei at collider energies. We find no g
ap in the rapidity distribution around mid-rapidity even at RHIC energ
ies (square-root s = 200 AGeV), but rather strong filling of the mid-r
apidity region. Neither is there a broad plateau for secondaries nor a
re the correlations between space-time and momentum as strong as in th
e Bjorken-McLarren scenario. This renders the Bjorken picture question
able at these energies for systems of combined mass A almost-equal-to
400.