Vaadin 7.1 using Jetty 9.1 errors

For some reason I just cannot get this combination to work.

There are Atmosphere issues like this:
Comet support class org.atmosphere.container.Jetty Async SupportWith WebSocket has bad signature

I have tried setting a dependancy on the latest Atmosphere, as well as adding

as has been suggested.

Any suggestions on how to get Vaadin 7.1 and Jetty 9.1 working together using maven?

Jetty 9.0.0.v20130308 and 9.0.4.v20130625 both appear to work ok.
Jetty 9.1.0.M0 does not.

Yes, me too, do tell if you get a good answer. I just went back to using Jetty 8, fine for my dev uses.