Pre-population more than one user in a apprequest

How can I pre-populate more than a user in the "to" section of a apprequest (same as you can find in Zinga's Citt开发者_如何学PythonyVille gift request)? I tried many methods, including assigning an array in the "to" param - resulting with an Error 100: To many recipients message.

As the message say, there is to many recipients :)

There is a maximum of 50 recipients.

My guess is that you need to be whitelisted by Facebook to get this sort of super power. The Sims Social are using the same parameters as you do but have the ability to specify multiple recipients. You should ask Facebook to do the same for your app.

See also How to create requests dialog with multiple recipients selected by app