function checkAll(form)
{
	el = form.elements;
    for (i=0;i < el.length;i++) {
        if(el[i].type.toLowerCase()=="checkbox") {
            el[i].checked = true;
        }
    }
}

function hasSelectedCheckboxes(form)
{
    el = form.elements;
    for (i=0;i < el.length;i++) {
        if(el[i].type.toLowerCase()=="checkbox" && el[i].checked) {
            return true;
        }
    }
    return false;
}