Some help with a Cipher please.

I'm not too sure where to put this so here will do for now, I have come across an interesting cipher that i have no idea on solving and was wondering if anybody else could give it a crack.

The cipher is:

NBJTFPEAOEQSJTEOGKVEFUEPRXQYEQKLKNFTOFBJLBLE

and here is a link to a picture of it.

Do we have to decipher the code to get the joke?