I think the next step would be to delete vmmi and reinstall it.Make sure your installing the same version of vmmi that the switch is on, for testing purpose.
Question: Do you have a NT/2000 voicemail on your systems?
If so, maybe the work around would be dial into it with pcanywhere and use the vmmi on it.
I am assuming you have a spare direct connection going to the sytem for vmmi off of the voicemail.
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