HTML5-video - autoplay

HTML

<video autobuffer controls autoplay id="myVideo">
  <source id="mp4" src="http://grochtdreis.de/fuer-jsfiddle/video/sintel_trailer-480.mp4" type="video/mp4">
</video>

CSS

html {padding: 20px 0; background-color: #efefef;}
body {width: 400px; padding: 40px; margin: 0 auto; background: #fff; box-shadow: 1px 1px 5px rgba(0,0,0,0.5);}

video {
    width: 400px; 
    display: block;
}

JavaScript

function listen(evnt, elem, func) {
    if (elem.addEventListener) // W3C DOM
    elem.addEventListener(evnt, func, false);
    else if (elem.attachEvent) { // IE DOM
        var r = elem.attachEvent("on" + evnt, func);
        return r;
    }
    else window.alert('I\'m sorry, I\'m afraid I can\'t do that.');
}

listen("ended", document.getElementById('myVideo'), DoSomething);

function DoSomething() {
    alert("Ended!");
}