function forceAgent(agent) {
  var a = "PC";
  if (agent == "iPhone") {
    a = "iPhone";
  }
  jQuery.cookie("forcedAgent", a, { path: "/" });
  window.location = (a == "iPhone") ? "/i/" : "/";
}

jQuery(".agentSwitch #iPhone").click(function() { forceAgent("iPhone"); });
jQuery(".agentSwitch #PC").click(function() { forceAgent("PC"); });