function checkSelection(objID, listObjName) {
	var obj = document.getElementById(objID);
	var listObj = document.getElementsByName(listObjName);
	
	if (obj.checked) {
		//select all the listed items
		for (i = 0; i < listObj.length; i++) {
			listObj[i].checked = true;
		}
	} else {
		//de-select all the listed items
		for (i = 0; i < listObj.length; i++) {
			listObj[i].checked = false;
		}
	}
}