defaultStep=1
step=defaultStep 

function scrollDivDown(id){
clearTimeout(timerDown) 
document.getElementById(id).scrollTop+=step 
timerDown=setTimeout("scrollDivDown('"+id+"')",10)

} 

function scrollDivUp(id){
clearTimeout(timerUp)
document.getElementById(id).scrollTop-=step 
timerUp=setTimeout("scrollDivUp('"+id+"')",10)
} 

timerDown="" 
timerUp="" 

function stopMe(){
clearTimeout(timerDown) 
clearTimeout(timerUp)
}

/*document.onmousemove=function(){stopMe()}*/

function roll(img_name1, img_src1)
{
document[img_name1].src = img_src1;
}