function IEVersion()
{
	var version = -1;

	if(navigator.appName == 'Microsoft Internet Explorer')
	{
		if(RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})").exec(navigator.userAgent) != null)
		{
			version = parseFloat(RegExp.$1);
		}
	}

	return version;
}