The guys over at SpringIDE have done quite a bit of work to support spring web flow:
http://springide.org/project/wiki/WebFlowEditor
It would be nice to see this integrated, or at the very least make sure the plugin won’t conflict with the spring stuff in MyEclipse.
Web flow and the ide are still in beta, but they are set for a 1.0 release very soon. My company is certainly looking to use it on my next project.
Cheers,
Jon