tooltip = null;

document.onmousemove = updateTooltip;

function updateTooltip(e) 
{
  try {
    x = (document.all) ? window.event.x + document.documentElement.scrollLeft : e.pageX;
    y = (document.all) ? window.event.y + document.documentElement.scrollTop : e.pageY;

    if (tooltip != null) 
    {
      tooltip.style.left = (x + 10) + "px";
      tooltip.style.top = (y - 50) + "px";
    }

  } catch (error) { error=null; }
}

function showTooltip(id) 
{
  try {
    tooltip = document.getElementById(id);
    tooltip.style.display = "block"
  } catch (error) { error=null; }
}

function hideTooltip() {
try {
tooltip.style.display = "none";
} catch (error) { error=null; }
}