A system and method for non-speech input or keypad-aided word and spelling
recognition is disclosed. The method comprises performing spelling
recognition via automatic speech recognition (ASR) on received speech
from a user, the ASR being performed using a statistical letter model
trained on domain data and producing a letter lattice R.sub.LN. If an ASR
confidence is below a predetermined level, then the method comprises
receiving non-speech input from the user, generating a keypad constraint
grammar K and generating a letter string based on a composition of finite
state transducers R.sub.LN and K. Other variations of the invention
include recognizing input by first receiving non-speech input,
dynamically generating an unweighted grammar, generating a weighted
grammar using domain data, and then performing speech, and thus spelling,
recognition on input speech using the weighted grammar.