var DownStep = 5;
var UpStep = -5;
var tID;
var tID2;

function StartUpScroll() {
tID2 = setInterval("StartUpScroll2()",10);
}

function StartUpScroll2() {
if(window.somename && window.somename.scrollBy) {
var ifr = window.somename;
if (ifr.document.body.scrollTop <= 0) {
clearInterval(tID2);
} else {
ifr.scrollBy(0, UpStep);
}
}
}

function StopUpScroll() {
clearInterval(tID2);
}

function StartDownScroll() {
tID = setInterval("StartDownScroll2()",10);
}

function StartDownScroll2() {
if (window.somename && window.somename.scrollBy) {
var ifr = window.somename;
if (ifr.document.body.scrollHeight - ifr.document.body.scrollTop <= ifr. document.body.offsetHeight) {
clearInterval(tID);
} else {
ifr.scrollBy(0, DownStep);
}
}
}

function StopDownScroll() {
clearInterval(tID);
}