Not sure if you guys are aware of this already, but you might want to add Struts 2 to this list as well. Seems they have SWF integrated through a plugin. Check out these for more info:
sebastien dionne - 22/Oct/08 08:37 PM is it ready to test ?
I try the plugin for struts2+webflow2, but it's not working yet. So I start looking for alternative.
https://issues.apache.org/struts/browse/WW-1525
http://cwiki.apache.org/S2PLUGINS/spring-webflow-plugin.html