step = 2;
interval = 20;

function startMarquee (elID)
{
 // get elements
 el = document.getElementById(elID);
 //parentEl = el.parentElement;

 // setup initial props
 el.style.position = "relative";
 el.style.display = "inline";
 el.style.left = "866px";//parseInt(parentEl.offsetWidth) + "px";
 //alert(el.style.left);

 // setup events
if (el.addEventListener) {
el.addEventListener ("mouseover",slow,false);
el.addEventListener ("mouseout",fast,false);
} else if (el.attachEvent) {
el.attachEvent ("onmouseover",slow);
el.attachEvent ("onmouseout",fast);
} else {
el.onmouseover = slow;
el.onmouseout = fast;
}
 // start marquee
 setInterval("stepMarquee('" + elID + "')", interval);
}

function slow()
{
 step = 1;
}

function fast()
{
 step = 2;
}

function stepMarquee(elID)
{
 // get elements
 el = document.getElementById(elID);
 //parentEl = el.parentElement;

 // step element
 lastPos = parseInt(el.style.left);
 lastPos -= step;
 if (lastPos < 0 - parseInt(el.offsetWidth))
  lastPos = 866;//el.parentElement.clientWidth;

 el.style.left = lastPos + "px";
}