1. A method for recognizing natural language speech utterances, comprising: receiving a natural language speech utterance from a user; determining an identity of the user by comparing voice characteristics of the received utterance to one or more user profiles; recognizing one or more words or phrases contained in the received utterance using at least one dictionary and phrase table, wherein the at least one dictionary and phrase table includes a plurality of entries associated with a dynamic set of prior probabilities or fuzzy possibilities; updating the dynamic set of prior probabilities or fuzzy possibilities based on a confidence level for the recognized words or phrases; requesting, based on the confidence level for the recognized words or phrases, a phonetic alphabet spelling for unrecognized or out-of-vocabulary words or phrases in the received utterance, the phonetic alphabet spelling provided by the user in one or more subsequent natural language utterances; and associating the identity of the user with a recognition of the received natural language utterance, wherein the recognition includes the recognized words or phrases, and further includes the phonetic alphabet spelling for the unrecognized or out-of-vocabulary words or phrases.