What happens when you mix a nerd’s sense of humor with a display iPhone 4S in a shop not necessarily known for its technical prowess? In at least one case, you get Siri appearing to curse out a twelve year old boy in a UK supermarket.

The Sun reported that young Charlie Le Quesne approached an iPhone 4S on display at the Tesco in Coventry and asked Siri, “How many people are there in the world?”

Siri’s alleged response: “Shut the f*** up, you ugly t***.”

Now, we all know that Siri can be a bit cheeky sometimes, but such a reply is surely beyond the pale, no? That’s what Charlie’s mum, Kim, thought, at least.

She told The Sun, “The phone was a demo version and was low enough on the shelf for Charlie to have a go with it. He asked it a simple question and we couldn’t believe the filth it came out with. I thought I must be hearing things. So we asked again and the same four-letter stuff blared out. I asked for the manager and after staff heard it they agreed to unplug it.”

It turns out that some enterprising nerd set the iPhone to have a user name of, “Shut the f*** up, you ugly t***.” That’s seven words, for those keeping score at home.

In other words, Siri wasn’t so much ordering a twelve year old boy around and bandying about profanity like Lady Sovereign on a drunken bender. Instead, she was addressing her master, whom she had been told to believe was named “Shut the f*** up, you ugly t***.”

What remains to be determined is when and where this prankster’s tampering took place. The Sun suggested it could have happened on an assembly line, but that seems unlikely. What is more believable is that someone did it after the device was set up and put on display.

In the meanwhile, Tesco took the device off the shelf and packed it off to Apple for testing.