So the guy says to the doctor: [deep, husky bark]"It's my voice. It's been like this since I was a teenager. People stare at me when I speak; my friends all take the mickey out of me; I can't stand it any longer. Is there anything you can do doctor?"

The doctor says: "Do you know, I've read about this and I've an idea what it might be. I'll have to carry out an examination – drop your trousers."

The chap drops his trousers, and an enormous penis flops out and thumps onto the desk. "Ah," says the doctor. "Just what I thought. Your enormous member is pulling your internal organs down, and puting strain on your vocal cords, which is affecting your voice. It's easy to put right – just a simple transplant operation. Do you want to go ahead with it?"

"Oh, yes please," barks the relieved patient. "Anything to put an end to this."

Two months later the man walks back into the surgery. "Doctor, it's incredible," he says. "You were right. Listen to me – my voice sounds normal. No one takes the mickey, I sound just like everyone else, I can join in karaoke – in fact I'm joining a choir. Life is fantastic.

"The only problem now is that my wife is threatening to leave me. She says that since my operation I can't satisfy her any more. Is there anything you can do about that?"

"No," barks the doctor. "There isn't."