function toggleReply ( replyID )
{
  reply = document.getElementById( 'rb' + replyID );
  if ( reply ) { // false if top-level node
    if ( reply.style.display == 'none' ) {
      reply.style.display = ''; // default
    } else {
      reply.style.display = 'none';
    }
  }

  replieslist = document.getElementById( 'rl' + replyID );
  if ( replieslist ) { // false if node has no replies
    if ( replieslist.style.display == 'none' ) {
      replieslist.style.display = ''; // default
    } else {
      replieslist.style.display = 'none';
    }
  }
}

function doNothing () { }