In the US, that is a common blonde joke.
Chad Fernandez
Michigan, USA
der Mouse wrote:
One day, the message-of-the-day had a Newfie joke in
it. (I think it
was "How do you know when a Newfie has used your word processor? When
there's white-out on the screen.".) Our resident Newfie told us "You
better be careful with those Newfie jokes - some of us might understand
them!".