It is not possible to set custom message composer on jca binding.

Message composer for JCA is obtained from class AbstractInflowEndpoint (https://github.com/jboss-switchyard/components/blob/master/jca/src/main/java/org/switchyard/component/jca/endpoint/AbstractInflowEndpoint.java) on line 214. But only binding data class is used in getMessageComposer call. Therefore default composer is returned all the times.

Changing it to: JCAComposition.getMessageComposer(_jcaBindingModel,clazz) uses also configuration value of composer class.