dont know his name but i heard it off a fellow spotter at BHX :
AF was en route to SYD flying the A 340 and the control tower said:
have you got a problem you seem to be going pretty slow for a 4 engined aircraft. Are you sure your aircraft is not an A330.
The pilots looked at each other and the pilot said :
” no we are deffinately an A340 because the airline does not have A330’s (at this time)/.
The control tower then came back saying:
” well can you hurry up and turn your other 2 engines on then please”