1. A method for authenticating a user, comprising: prompting a user for a free-form password in a password establishment dialog; receiving a user utterance; processing the utterance through a speech recognition engine to generate an acoustic baseform; associating the user with the acoustic baseform in a speaker-dependent password recognition grammar; matching, in a password usage dialog, user utterances against the acoustic baseform in the speaker-dependent password recognition grammar associated with the user, the matching thereby verifying both the free-form password and the user that provided the user utterance; and using results from the matching to determine whether to grant the user access to a secure resource.