Automatically shortening URL for Email/Facebook shares with Bitly through AddThis API

问题

I am unable to shorten the URL being shown in the AddThis email popup when using the built-in Bit.ly shortening service in AddThis.

It works with Twitter, but not Facebook and email. Is this supported?

var addthis_share = {
    url: "http://www.wrestlemaniamainevent.com/wishlist/kjhksad897dsjkhdsa98273",
    title: "View My List",
    url_transforms: {
        shorten: {
            twitter: 'bitly',
            facebook: 'bitly', // Unsupported?
            email: 'bitly' // Unsupported?
        }
    },
    shorteners: {
        bitly: {
            login: '{login}',
            apiKey: '{key}'
        }
    }
}

来源：https://stackoverflow.com/questions/27148711/automatically-shortening-url-for-email-facebook-shares-with-bitly-through-addthi