Crazy Rabbit

A rabbit enters a bar and orders, "One beer, you jackass."
The barman gives him what he wants without saying anything.
Next day the rabbit comes again. "One beer, you jackass."
This time the barman says (after giving him his beer),
"Just call me a jackass once more and I will take two nails and nail your ears on the door."
Next day the rabbit comes again into the bar and asks, "Do you have nails?"
"No", says the barman.
"Then give me one beer, you jackass!"