function mouseX(evt) {
	return evt.clientX ? evt.clientX + (document.documentElement.scrollLeft || document.body.scrollLeft) : evt.pageX;
}

function mouseY(evt) {
	return evt.clientY ? evt.clientY + (document.documentElement.scrollTop || document.body.scrollTop) : evt.pageY
} 

function tooltip(id, state, event)
{
	el = document.getElementById(id);
	el.style.left=  mouseX(event)+12+"px";
	el.style.top=  mouseY(event)+12+"px";
	el.style.visibility= state;
}

function tipUp(id, event)
{
	tooltip(id, 'visible', event);
}

function tipDown(id, event)
{
	tooltip(id, 'hidden', event);
}