var scrolling = new Object();
var scrollWith = new Object();

function scrollInit()
{

    if(document)
    {
        for ( keyVar in scrolling ) {
           if(scrolling[keyVar])
           {
                var div = document.getElementById(keyVar);
                if(div != null){
                    div.scrollTop = div.scrollTop + scrollWith[keyVar];
                }
           }
        }	
	}
	t = setTimeout('scrollInit()', 15);
}

scrollInit();

function startScrolling(elemname, sw){
    scrolling[elemname] = true;
	scrollWith[elemname]  = sw;
}

function stopScrolling(elemname){
	scrolling[elemname] = false;
}

function toggleScrollbar(elemname, navup, navdown){
    var element = document.getElementById(elemname);
    var up = document.getElementById(navup);
    var down = document.getElementById(navdown);
    
    if (element.clientHeight >= element.scrollHeight)
    {
        up.style.display = 'none';     
        down.style.display = 'none';
    }
}