function selectDeselectCheckBoxes(parentCtl, checked) {
    var ctl;
    var ctls;
           
    ctl = document.getElementById(parentCtl);    
    ctls = ctl.getElementsByTagName('input');
    
    for (var i = 0; i < ctls.length; i++) {
        ctls[i].checked = checked;
    }
    
    return true;
}