I meant to say, my ejb-deployer.xml contains
Sorry, it looks like I may have jumped the gun when I posted this question. Apparently call-by-value is being used in both cases... that fact was just obfuscated by the way the EJB code is written.
Now I just have to figure out why pass-by-value is always being used with these local invocations. I modified ejb-deployer.xml but it had no impact...