Need to use JQuery UI if you want to animate things like borderColor, or straight up pass in class styles as params.
_ http://jqueryui.com/demos/switchClass/#default

This function was actually a pain in the ass to use, if you're dealing with a tangled stylesheet where more than 1 class is responsible for an element's style at any given time. Point is, it can require some tailoring if the css isn't straightforward. In the end border color was ditched.