Using Google's mail I have programmatic access to all sorts of settings via the API. http://code.google.com/intl/en/googleapps/domain/email_settings/developers_guide_protocol.html
I can't find anything similar for Hotmail / Live email - even Custom Live Domains doesn't seem to give me any of this.
Is it really just not available at all or am I just being dumb?
It turns out that there is no API provided to do this yet. How MS expect people to use Custom Domains without it is beyond my comprehension, but I'm sure they know what they're doing.