flag = false;

function toggleAll () {
	ref = document.forms [0];
	//state = ref.toggle.checked;
	flag = !flag;
	for (i = 0; i < ref.length; i++) {
		if ((ref.elements [i].name.indexOf ("a") == 0) && (ref.elements [i].type == "checkbox")) {
			ref.elements [i].checked = flag; //state;
		}
	}
}