Cornell John Cast as Glenstorm
From Narnia.com:
The final key role has been cast – Glenstorm the Centaur. British stage actor Cornell John, whose recent London stage roles include such high-profile musical productions as Les Miserables, The Full Monty, and Disney’s The Lion King, will play the half man, half horse.
Now, I know what everyone is thinking after reading the final key role. “What about Reepicheep?” We know that Reep will make an appearance in Prince Caspian as stated here by Douglas Gresham. I suspect that Reep simply doesn’t qualify as a “key role” in Prince Caspian but has not been removed from the movie.