function cookie_check_support() 
{	
	cookie_add_value("check","OK");
	if(cookie_get_value("check") == false) {
		return false;
	}
	cookie_delete("check");
	return true;
}

function cookie_delete(name)
{
	document.cookie = name + "=; expires=Thu, 01-Jan-70 00:00:01 GMT";
}

function cookie_get_value(name)
{
	var value = null;	
	if(document.cookie != "") {
		var pos_name = document.cookie.indexOf(name + "=");
		if(pos_name >= 0) {
			pos_name = pos_name + name.length + 1;
			var pos_semikolon = document.cookie.indexOf(";", pos_name);
			if(pos_semikolon < 0) {
				pos_semikolon = document.cookie.length;
			}
			value = document.cookie.substring(pos_name, pos_semikolon);
			value = unescape(value);
		}
	}
	return value;
}

function cookie_add_value(name, value)
{
	var today = new Date();
	var expires = new Date();
	expires.setTime(today.getTime() + 1000*3600*24*365); /* save cookie 1 year */

	if(document.cookie != "") {
		var pos_name = document.cookie.indexOf(name + "=");
		if(pos_name >= 0) {
			pos_name = pos_name + name.length + 1;
			var pos_semikolon = document.cookie.indexOf(";", pos_name);
			if(pos_semikolon < 0) {
				pos_semikolon = document.cookie.length;
			}
			var f = document.cookie.substring(pos_name, pos_semikolon);
			f = f + escape(value);
			document.cookie = name + "=" + f + "; expires=" + expires.toGMTString();
			return;
		}
	}
	
	document.cookie = name + "=" + value + "; expires=" + expires.toGMTString();
}