var scrollAmount=10;
var scrollWaitTime=35;
var scrollTimeOut; //declared global 

function scroll(direction){
   window.frames['content-frame'].scrollBy(0,direction*scrollAmount);
   scrollTimeOut = setTimeout('scroll('+direction+')',scrollWaitTime);
}

function scrollUp(){
 scroll(-1);
}

function scrollDown(){
 scroll(1);
}

function scrollStop(){
	if (scrollTimeOut) clearTimeout(scrollTimeOut);
}