Facebook user's email address is...?

I've got an object that represents an email, and I'd like to send it a开发者_StackOverflow中文版s a message to a user on Facebook. What email address do I use as the destination for this email that will be received as a message on Facebook?

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You need to request a special pemission to send email to a facebook user.

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In the "good news" department, Facebook has announced that soon you'll be able to email users with much less fuss:

http://wiki.developers.facebook.com/index.php/Roadmap_Email

The timing hasn't been fully revealed yet, but supposedly, soon!