We extend the equation of state of GCG ( Generalized Chaplygin Gas ) to w < -1 regime and show , from the point of view of dynamics , that the parameters of GCG should be in the range of 0 < \alpha < 1 .
Also , dynamical analysis indicate that the phase w _ { g } = -1 is a dynamical attractor and the equation of state of GCG approaches it from either w _ { g } > -1 or w _ { g } < -1 depending on the choice of its initial cosmic density parameter and the ratio of pressure to critical energy density .