function post_redirect (url, params) {
	var f = document.createElement('form');
	f.method = 'POST';
	f.action = url;
	
	for (var name in params) {
		var value = params[name];
		if (typeof value == 'function') continue;
		
		var el = document.createElement('input');
		el.type = 'hidden';
		el.name = name;
		el.value = value;
		f.appendChild(el);
	}
	
	document.body.appendChild(f);
	f.submit();
}