var Timer;

function ScrollUp()
{
  document.getElementById("scrollButtonUp").style.backgroundImage = "url(/images/scroll_up2.gif)";
  Timer = setInterval("document.getElementById('scroller').scrollTop -= 4", 15);
}
function ScrollDown()
{
  document.getElementById("scrollButtonDown").style.backgroundImage = "url(/images/scroll_down2.gif)";
  Timer = setInterval("document.getElementById('scroller').scrollTop += 4", 15);
}


function clearUp() {
  clearInterval(Timer);
  document.getElementById("scrollButtonUp").style.backgroundImage = "url(/images/scroll_up.gif)";
}

function clearDown() {
  clearInterval(Timer);
  document.getElementById("scrollButtonDown").style.backgroundImage = "url(/images/scroll_down.gif)";
}