Is it possible to add an alternate pronunciation for an existing word in the vocabulary?
No. Not directly, but ViaVoice for Windows will recognize that you are having misrecognition problems after correcting the same word a few times and will prompt you for a new pronunciation for that word. There are exceptions to this rule for words such as ‘a’, ‘an’, ‘the’ and other very common words. You can also create a macro for this word and train it with an alternate pronunciation.