I know it's not there yet for M1. Not sure about its status for M2. Stay tuned.
I can verify that EL 2.2 (the one that supports method parameters) is included in JBoss AS 6.0.0.M2. I just tried the following expression and it worked out of the box:
(of course there is a shorthand for that, but it was just a proof of concept).
thanks for the update. I'll check it soon.