51. The system of claim 44 , wherein the means for adjusting the voice prompt adjusts the prosody of the voice prompt to use prosody that is consistent with the determined state of the user.
44. A system adjusting a voice prompt based upon a state of a user of the system, the system comprising: means for obtaining utterance parameters from utterance received from the user, the utterance parameters indicating the state of the user; means for determining the state of the user based upon the utterance parameters; and means for adjusting the voice prompt by adjusting at least one of a tone of voice of the voice prompt, a content of the voice prompt, a prosody of the voice prompt, and a gender of the voice prompt based upon the determined state of the user, wherein the means for obtaining utterance parameters comprises: means for partitioning the utterance into segments; and means for assigning one of a plurality of classifications to each segment, each classification corresponding to at least one of a plurality of states of the user, wherein the means for determining the state of the user based upon the utterance comprises: means for generating an utterance parameter vector based upon the utterance parameter by (1) determining the number of segments for each classification, and (2) dividing the number of segments for each classification by a total number of segments in the utterance.