var scrollObject = null;
var scrollDirection = 0;
var scrollAmount = 12; 
var scrollTimeout = 50;

function scrollDo() {
   if ((scrollObject != null) && (scrollDirection != 0)) {
      scrollObject.scrollTop = scrollObject.scrollTop + (scrollAmount * scrollDirection);
      window.setTimeout("scrollDo();", scrollTimeout);  
   } else {
      scrollStop();
   }
}

function scrollStart(obj, direction) {
   // Finds the parent
   while ((obj != document) && (obj.getAttribute('scrollTo') == null)) {
      obj = obj.parentNode;
   }
   
   if (obj == document) {
      return;
   }
   
   scrollObject = document.getElementById(obj.getAttribute('scrollTo'));
   scrollDirection = direction;
   scrollDo();
}

function scrollStop() {
   scrollObject = null;
   scrollDirection = 0;
}