function overlayOn(thingy)
{
  document.getElementById(thingy).style.background="url('images/front_page_people/darkoverlay.gif')";  
}

function overlayOff(thingy)
{
  document.getElementById(thingy).style.background="url('images/front_page_people/blueoverlay.gif')";  
}

function check(theCheckbox) {
  var y = document.getElementById(theCheckbox);
  
  if(y.checked)
    y.checked = false;
  else
    y.checked = true;
  
}


function CheckAll (id, checked) {
	var el = document.getElementById(id);
	for (var i = 0; i < el.elements.length; i++) {
	  el.elements[i].checked = checked;
	}
}