No, that usually happens because of request-scoped bean usage. The problem with request-scoped beans is that on postback they reset their values to the initial one so JSF processes the first panel group component instead the second.
You can try to add
<a4j:keepAlive beanName="TestBean"/>if that is the case
Yes! That's exactly what my problem was!
Thanks very much - I was using keepAlive earlier for most of the site and took it off when I *thought* it wasn't necessary anymore.