Unwanted Contact Sync

When importing contacts into Windows Live Mail, Windows Live Messenger
automatically seems to sync those contacts (at least those with a hotmail.com
address).

This is annoying for several reasons:
a) Everyone using Messenger on your lists gets an "accept/decline" message
b) This includes people you may have never met for instance but simply
added their contact
c) There's no indication that this will happen, and as far as I can tell
no way to turn it off

There are probably others, but these were the ones that came to me off the
top of my head.

It'd be nice if there was some option either in Messenger itself, or in Mail
to turn off this sort of contact sync.

Thanks

Alex