Well, there is Turn Undead... doesn't banish them, but makes them turn and run away, like Word of Fear does. That drops from Pantera in Froz. Labyrinth.
Then there is Erase, which kills (unsummons) a summon. Maybe that is what you mean?? That also drops in Frozen Labyrinth but by the Elder Lost Watcher.
Nope, its a Pally skill that was added for C5. No sb needed. I've been using it some... have found it next to useless right now, but maybe as it gains levels?!?! I guess I'll have to wait and see.