As you might have seen already: http://xmpp.org/2011/09/microsoft-adds-xmpp-support-to-windows-live-apis/
With some hard-coded hackery to fake the custom authentication I've managed to sign in. Although I don't know exactly how Facebook's auth works, it seems pretty similar to me (open a webview with an URL, get a token and use that to sign in). From the little bit of testing I did, it appears this works: sending messages, some avatars, status messages, etc (though it seems display name and real name are swapped). And this doesn't: file transfers, federation. So yeah, it seems to be almost as good as libpurple's msn support as of recently. ;) Thijs
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