var timer_id;
function scroll_iframe(frm,inc) {
if (timer_id) clearTimeout(timer_id);
if (window.frames[frm]) {
window.frames[frm].scrollBy(0, inc);
timer_id = setTimeout("scroll_iframe('" + frm + "'," + inc + ")", 20);
}
}

function stopScroll() { if (timer_id) clearTimeout(timer_id); }