Inviting users to a pre-existing facebook event using the REST API

What is the best way to invite users to an existing event? We'd like to do the following:

create an event, make it public
while on our (external) website give the user a dialog (fb:multi-friend-selector) to select their friends to invite to the event

It's established the new Graph API can't be used (http://bugs.developers.facebook.net/show_bug.cgi?id=10070), but the documentation for the REST API (http://developers.facebook.com/docs/reference/rest/events.invite) implies that it's not possible to invite users to existing events.

If anyone could provide any clarity on this I'd be grateful - reading the vague and contradictory facebook documentation is getting me nowhere.

Specifically, who/where/how should the event be created? - and how can I then invite users to that event from an external website?

Solution

This can be done using the Graph API. To use the JavaScript SDK use the following:

FB.api('/[EVENT-ID-HERE]/attending', 'post');

This can only be done once you have an authenticated user, so in full, the code would be:

<div id="fb-root"></div>
<script src="http://connect.facebook.net/en_US/all.js"></script>
<script>
FB.init({
    appId: '[APP-ID-HERE]', cookie: true, status: true, xfbml: true
});
FB.Event.subscribe('auth.login', function (response) {
    if (response.session) {
        FB.api('/[EVENT-ID-HERE]/attending', 'post');
    }
});
</script>       
<fb:login-button perms="rsvp_event">Attend Event</fb:login-button>