Quote Originally Posted by peaches View Post
WoW had it implemented as well. If you were playing a class that could cover multiple roles with a simple Spec change, it would let you queue for any of the roles you have unlocked.

It could work exactly the same way it does now - it lets you play as a different class while you're waiting in queue as a different one right? And it restricts you from entering until you're on the correct role.

So all it has to do is let you queue as multiple, and what ever spot your character end up filling, you wouldn't be able to enter the instance until you switch to the proper job.
Rift did the same also.