function select_all_check(listid){
	var where_form = document.getElementById('where_form');
	
	var boxes = where_form.getElementsByTagName('input');
	
	for(var i = 0; i < boxes.length; i ++)
		{
			if(boxes[i].getAttribute('type') == 'checkbox')
				{
					boxes[i].setAttribute('checked','checked');
				}
		}
}