  The role of brane-bulk energy exchange and of an induced gravity term on a
single braneworld of negative tension and vanishing effective cosmological
constant is studied. It is shown that for the physically interesting cases of
dust and radiation a unique global attractor which can realize our present
universe (accelerating and 0<Omega_{m0}<1) exists for a wide range of the
parameters of the model. For Omega_{m0}=0.3, independently of the other
parameters, the model predicts that the equation of state for the dark energy
today is w_{DE,0}=-1.4, while Omega_{m0}=0.03 leads to w_{DE,0}=-1.03. In
addition, during its evolution, w_{DE} crosses the w_{DE}=-1 line to smaller
values.
