Managed folder

We need to create a new managed folder contains a URL for user access to their archived email (hosted by a 3rd party).

I don't see how to do this anywhere in the exchange documentation. 

We are able to create this folder on the Outlook client itself, but surely there's a way to push out a managed folder of this type from EMC, or more specifically for exchange 2010, the powershell.

Thank you!