I'm a little lost on how this would be useful. Granted, I shunned EJB before Seam and am definitely no expert, but wouldn't remote services generally be used by your local EJB actions rather than resolved via EL within pages? I'm pretty sure you can inject a remote EJB using the @EJB annotation and I'd imagine if you really need one from within a JSF page it would be pretty simple to write your own resolver...
I've heard this request several times. You should definitely put in JIRA for consideration.