Hey, I was poking around with an idea of a button that animates when hovering over, but seems like what's really needed is a mouseneter-like behavior. Here's the scenario:

The button has a ellipse background and an icon in the middle of it - they are not a group since I only need to animate the ellipse. I'm attaching a listener to the canvas hoping the whole canvas will be a hot-spot, instead the ellipse, and the icons are (separately). You can notice the flickering when moving your mouse.

See this example: http://jsfiddle.net/oskar/A5cmN/