Best read with a Japanese accent: Nelson Mandela is at home watching TV when
there is a knock at the door. A Japanese delivery man is clutching a clipboard,
pointing to a truck full of car exhausts in the driveway and yelling, "You
sign, you sign!" 
The bewildered president will do no such thing and slams
the door. 
The next day, the man is back, waving a clipboard under the great
man's nose, gesturing to a truckload of brake pads and insisting, "You
sign, you sign!" 
Nelson gets rid of the man again, but next day he's back
with two truckloads of car parts, once again insisting that the president sign
for the goods. Mandela loses his temper and yells, "Look, I don't want
these. Do you understand? You have the wrong person." 
Puzzled, the Japanese
man consults his clipboard and asks, "Ah soh. You not Nissan Maindealer?"