Provider org.atmosphere.cpr.AnnotationScanningServletContainerInitializer not a subtype

[mejmo]

Hello,

we are getting this error on Webspher 8.5 and Vaadin 7.7.3. There is a problem with atmosphere initialization, but I was unable to find a solution. May you give us a hint?

Caused by: java.util.ServiceConfigurationError: javax.servlet.ServletContainerInitializer: Provider org.atmosphere.cpr.AnnotationScanningServletContainerInitializer not a subtype
	at java.util.ServiceLoader.fail(ServiceLoader.java:242)
	at java.util.ServiceLoader.access$300(ServiceLoader.java:192)
	at java.util.ServiceLoader$LazyIterator.next(ServiceLoader.java:380)
	at java.util.ServiceLoader$1.next(ServiceLoader.java:456)
	at com.ibm.ws.webcontainer.webapp.WebAppImpl.initializeServletContainerInitializers(WebAppImpl.java:535)
	at com.ibm.ws.webcontainer.webapp.WebAppImpl.initialize(WebAppImpl.java:409)
	at com.ibm.ws.webcontainer.webapp.WebGroupImpl.addWebApplication(WebGroupImpl.java:88)
	at com.ibm.ws.webcontainer.VirtualHostImpl.addWebApplication(VirtualHostImpl.java:169)
	... 21 more