function isPDAAgent() {
  var br_name = navigator.appName;
  var br_version = navigator.appVersion;
  var br_codename = navigator.appCodeName;
  var br_agent = navigator.userAgent;

  var pda_agents = Array('Windows CE', 'NetFront', 'Palm OS', 'Blazer', 'Elaine', 'WAP', 'Plucker', 'AvantGo', 'Opera mini');


  if (GetInsideWindowHeight() < 480 && GetInsideWindowWidth() < 640)
    return true;

  for (var i = 0; i < pda_agents.length; i++) {
    if (br_agent.toString().ToLower().indexOf(pda_agents[i].toString().ToLower()) >= 0) {
      return true;
    } 
  }

  return false;
}