function ExpandMdpFields(){
   if(document.getElementById('ChangeMdp').style.display == 'block')
        {
        document.getElementById('ImgChangeMdp').src = '/images/expand_more.gif';
        document.getElementById('ChangeMdp').style.display = 'none';
        }
   else
        {
        document.getElementById('ImgChangeMdp').src = '/images/expand_less.gif';
        document.getElementById('ChangeMdp').style.display = 'block';
        }
}