function doIframe(){
    o = document.getElementsByTagName('iframe');
    for(i=0;i<o.length;i++){
        if (/\bautoHeight\b/.test(o[i].className)){
            setHeight(o[i]);
            addEvent(o[i],'load', doIframe);
        }
    }
}

function setHeight(e){
    if(e.contentDocument){
        e.height = e.contentDocument.body.offsetHeight + 35;
    } else {
        e.height = e.contentWindow.document.body.scrollHeight;
    }
}

function addEvent(obj, evType, fn){
    if(obj.addEventListener)
    {
        obj.addEventListener(evType, fn,false);
        return true;
    } else if (obj.attachEvent){
        var r = obj.attachEvent("on"+evType, fn);
        return r;
    } else {
        return false;
    }
}

if (document.getElementById && document.createTextNode){
    addEvent(window,'load', doIframe);	
}