[klavsdjb] Buffalo buffaloes Buffalo buffaloes buffalo buffalo Buffalo buffaloes.

The original sentence with repeated "buffalo" only works because of an unusual use of the word as a plural noun (agreeing with the plural verb) instead of the more common pluralization buffaloes.

Brown cats [that] black dogs buffalo buffalo white mice.

Or buffalo could be interpreted (again unusually) as a collective noun.

Jewish people [that] German people buffalo buffalo Palestinian people.