Wrong Dog

A nervous postman on his first round walked up to a garden fence. There was a large Doberman lying on the grass. An old man was sitting on the patio.

"Excuse me, sir, but does your dog bite?" the postman asked.

The old man replied, "No, he never has done."

So the opened the gate and went into the garden. The dog ran over snarling and growling and bit him on his arms and legs. As the old man dragged the dog off, the postman yelled, "I thought you said your dog didn't bite!"

The old man replied, "He's not my dog!