Vaadin with SpringMVC / REST Services

Hi!

We are running a Vaadin 7 App on Tomcat 7 and Java 8 (with an IBM data.
The application has a UI part and a webservice (REST) part both with the same services and persistence beneath.
The webservice was build using SpringMVC using @RestController and @RequestMapping
Everything worked fine until I had to migrate (for reasons..) from spring XML config to java-config. Now when I add  the @EnableWebMvc annotation to the spring context, it blows literally everything. Not even the unit tests are functional anymore. I read through the whole SpringMVC documentation and about 50 stak overflow pages and tried everyting...

Now to my questions:
Is anybody in the community who got that stuff running?
Have you got a Vaadin web app with an additional rest webservice? If so, how did you do it?

Best regards,
Christoph