function open_window(url,size) {

      agent = navigator.userAgent;
      windowName = "_blank";

      params  = "";
      params += "toolbar=0,";
      params += "location=0,";
      params += "directories=0,";
      params += "status=0,";
      params += "menubar=0,";
      params += "scrollbars=1,";
      params += "resizable=1,";
      if(size == 1)
        {
              params += "width=350,";
              params += "height=400";
        }
      else if (size == 2)
        {
              params += "width=450,";
              params += "height=550";
        }

      win = window.open(url, windowName , params);

      if (agent.indexOf("Mozilla/2") != -1 && agent.indexOf("Win") == -1) {
          win = window.open(url, windowName , params);
      }

      if (!win.opener) {
          win.opener = window;
      }
};