OnCollision messages don't work with Character Controller?

I feel like I ought to know this by now, but I never had a need to deal with it, and I'm not finding anything about it while searching. I just want to use OnCollisionEnter, and have it react to a CharacterController. Is that not possible? All I've got moving in my scene is a Character Controller, so it's a waste to have to check junk in OnControllerColliderHit.

It's not possible without adding a rigidbody onto your character controller, no. And then that's probably an even bigger waste