Service components created by the Mule object factories (all except <spring-object>) are not injected by Spring.
Also, the Mule XxxAware interfaces do not work (same reason I guess)
A workaround is to define the component as a Spring bean and reference it from the service component using the <spring-object ref="springId"> object factory.
This is by design, mule-core doesn't depend on spring and so object factories (except spring-object) do not use spring or create the instances as spring beans. I believe the Mule ServiceAware interface can be used anyway.