I have an issue I can't seem to track down. I am using Flot to graph some data, super easy. I want to add the hover effect you see here: [Flot Example](http://people.iola.dk/olau/flot/examples/interacting.html) 

Unfortunately, under no circumstance can I get the 'plothover' event to fire. This is a brief snippet from the code:

```
$.plot($chartArea, eventData, eventOptions);

$chartArea.bind("plothover", function (event, pos, item) {
    console.log('hovering!');
});

```

Is there something you need to set in the options object to enable this behavior? Thanks!