function checkIE6 () {
	var Browser = {
	  Version: function() {
	    var version = 999; // we assume a sane browser
	    if (navigator.appVersion.indexOf("MSIE") != -1)
	      // bah, IE again, lets downgrade version number
	      version = parseFloat(navigator.appVersion.split("MSIE")[1]);
	    return version;
	  }
	}
	if (Browser.Version() < 7) {
	  document.getElementById('warning_ie6').style.display='block';
	}
}