How to block multiple logins

How can I prevent users from being logged in on 2 different resources at the same time?

I've searched for it but I only found answers saying how you block users using the same login and the same resource. I want to close the first connection when the user connects again even if he's using a different resource.

Does anyone know how to configure Openfire to do it?

I'm using Openfire 3.8.2.

Thanks.