function clearregsession(url) {

  var navigator = this.navigator,
      isOldIE = navigator.appVersion.indexOf("MSIE") == -1 ? false : true,
      isOldOpera = navigator.userAgent.indexOf('Opera') != -1 ? true : false,
      temp;

	if (isOldIE) {
		temp = navigator.appVersion.split("MSIE");
		isOldIE = parseFloat(temp[1]) < 7;
	}

	if (isOldOpera || isOldIE) {
    try {
      if (window.jQuery) {
        jQuery.ajax({url: url});
      } else if (window.Prototype) {
        new Ajax.Request(url);
      }
    } catch (e) {}
	}
}