scalatra atmosphere example not working

[Jojo Low]

Hi ! 

It seems official websockets exemple is not working ( https://github.com/scalatra/scalatra-website-examples/tree/master/2.4/async/scalatra-atmosphere-example )

I am having this kind of error: 

15:03:08.665 [qtp883049899-38] ERROR o.a.interceptor.JavaScriptProtocol - Invalid Atmosphere Version 2.0.3-jquery

ava.lang.NullPointerException: null

        at org.scalatra.atmosphere.ScalatraAtmosphereHandler$$anonfun$onRequest$1$$anonfun$apply$1.apply(ScalatraAtmosphereHandler.scala:80) ~[scalatra-atmosphere_2.11-2.4.1.jar:2.4.1]

        at org.scalatra.ApiFormats$class.withRouteMultiParams(ApiFormats.scala:189) ~[scalatra_2.11-2.4.1.jar:2.4.1]

        at org.scalatra.example.atmosphere.ChatController.withRouteMultiParams(ChatController.scala:14) ~[scalatra-atmosphere-example_2.11-0.2.0-SNAPSHOT.jar:0.2.0-SNAPSHOT]

        at org.scalatra.atmosphere.ScalatraAtmosphereHandler$$anonfun$onRequest$1.apply(ScalatraAtmosphereHandler.scala:74) ~[scalatra-atmosphere_2.11-2.4.1.jar:2.4.1]

        at scala.util.DynamicVariable.withValue(DynamicVariable.scala:58) ~[scala-library-2.11.7.jar:na]

        at org.scalatra.DynamicScope$class.withResponse(DynamicScope.scala:78) ~[scalatra_2.11-2.4.1.jar:2.4.1]

............

Does anyone managed to have it working ?

Best regards ! 

Jojo