Injecting local EJB on JBoss 7.3 - @EJB vs @Inject

Question

I have an EAR file containing a WAR.

• The EAR contains an EJB jar. The EJB exposes a Local and Remote interface.

  @Stateless(name = "FooServiceEJB")
  @Local(IFooServiceLocal.class)
  @Remote(IFooService.class)
  public class FooServiceBean implements IFooService, IFooServiceLocal {
      ...
  }
  

• The WAR file defines a JAXRS annotated class.

  @Path("/foo")
  @LocalBean
  @Stateless
  public class FooResource {
     ...
  }
  

I wish to inject the local 'view' of the EJB into the JAXRS resource class. Apparently I have two options, which I assumed would be equivalent (for the most part):

1. Use @EJB
2. Use @Inject (To many, this appears to be the preferred option - see Should I use @EJB or @Inject)

I'm running JBoss EAP 6.2.0.GA (AS 7.3.0.Final-redhat-14).

The difference in behaviour that I am seeing is as follows (on JBoss - haven't tried any other app servers):

If I use @EJB to inject the local ejb, then the call semantics are by reference (as expected). For example:

@EJB
private FooServiceLocal fooService;

However, if I use @Inject to inject the local ejb, the call semantics are by value (i.e. serialization occurs). For example:

@Inject
private IFooServiceLocal fooService;

Here's a snapshot of the thread stack with the class that I believe is performing the serialization. The thread stack is completely different when I use the @EJB annoation.

https://i.stack.imgur.com/BXSaz.png

Any ideas why I am seeing this difference in behaviour?