  A modified spatial prisoner's dilemma game with voluntary participation in
Newman-Watts small-world networks is studied. Some reasonable ingredients are
introduced to the game evolutionary dynamics: each agent in the network is a
pure strategist and can only take one of three strategies (\emph {cooperator},
\emph {defector}, and \emph {loner}); its strategical transformation is
associated with both the number of strategical states and the magnitude of
average profits, which are adopted and acquired by its coplayers in the
previous round of play; a stochastic strategy mutation is applied when it gets
into the trouble of \emph {local commons} that the agent and its neighbors are
in the same state and get the same average payoffs. In the case of very low
temptation to defect, it is found that agents are willing to participate in the
game in typical small-world region and intensive collective oscillations arise
in more random region.
