facebook sdk and iap?

Maybe this is not the right place for my question but because it is an asset i have downloaded from the store i try it here.

I do not fiend the right informations on how to use iap for facebook games made with unity.
Can i do this with the official facebook sdk?

Or do i have to use other plugins like unibill or prime31?

I want to use an own currency in the game that players can buy in different packages in the facebook game.
How can i do that?

I read about the social features that are now possible and easy implemented in unity but i do not find the right information on how to get iap into a unity facebook game.

I think i have to use the extra plugins for mobiles but is there a native way from facebook?

Can someone help, please?

Anyone?