Hey Ed (and other interested parties) - yes Klingon is an official language. I think it is a bit more legitimate than Goa'uld or Vulcan because the language's creators have released a dictionary for public consumption and Klingon is used outside of Star Trek and related properties in places like Big Bang Theory and Frasier (which is ironic as Kelsey Grammer was in an episode of TNG). Hope this answers your question!
Now if only DC could get their act together and stick to a Kryptonian alphabet...
Ed Jones(XLIX)