One day, the wise men of Chelm decide to start making their own beer.
After months of experimentation with different recipes, they still can't agree which is the best formula. They deliberate for weeks, with no resolution. Finally they leave the decision to the Rabbi.
The Rabbi decides which one is their very best beer and the Chelmites ship a sample off to Warsaw for certification.
Two weeks later they get a telegram: "Your horse has diabetes."