Cats are interesting animals; although they are usually predatory animals to wild rabbits (the Easter Bunny needs to watch out) they will take kindly to bunnies that are house-trained.
Cats and rabbits interact just fine when they realize they are equals. They will play together and act just the same. Rabbit owners may see them using the litter box just like their feline friends.
Cats and rabbits can bond and play together outside although cats do not chew and rabbits do - so attention is a must. Rabbits teeth grow 3-5" inches annually and they will chew on hard surfaces.
Consider a cat fence with a metal bottom to prevent bunnies from burrowing underneath the fence and releasing from the other side.