Execute function when play button is clicked in html5 audio player

[Windbrand]

Is it possible to detect when the play button in the html5 audio player is clicked? For example:

<audio controls>
    <source src="music.mp3"/>
    <source src="music.ogg" />
</audio>
....
....
$('playbutton').on('click', function(e){
    //some functions
});

[rnd me]

http://www.quackit.com/html_5/tags/html_audio_tag.cfm

$(audio)[0].onplay= function(e){
    //some functions
};

[Windbrand]

I tried this but it doesn't do anything, no alert is produced when I click play button:

$(audio)[0].onplay= function(e){
    alert('playing');
};
...
...
<audio controls>
    <source src="music.mp3"/>
    <source src="music.ogg" />
</audio>

What is the [0] for?

[rnd me]

oops:

$('audio')[0].onplay= function(e){
    //some functions
};