I want to share with you our experience of using jameleon test framework.
It's a great test framework build over jUnit.
It has a plugin (jiffie) for running test scripts in the IE browser. The scripts are nothing more then an XML scripts with jameleon tags, which are quite simple in usage. Also jelly tags could be included for involving some specific actions. It's easy to extend, if you're using JSF for example for front-side, you may write custom tags for scripts where you can define custom elements and how to operate with them.
Another great advantage of it is that it's using XPath to analize and reach XHTML elements on the page.