  We investigate the effect of the bulk contents in the DGP braneworld on the
evolution of the universe. We find that although the pure DGP model cannot
accommodate the transition of the effective equation of state of dark energy,
once the bulk matter T^5_5 is considered, the modified model can realize the
w_{eff} crossing -1. However this transition of the equation of state cannot be
realized by just considering bulk-brane energy exchange or the GB effect while
the bulk matter contribution is not included. T^5_5 plays the major role in the
modified DGP model to have the w crossing -1 behavior. We show that our model
can describe the super-acceleration of our universe with the equation of state
of the effective dark energy and the Hubble parameter in agreement with
observations.
