How to batch export vaults to exchange mailboxes directly

We are running Vault 10.0.1 and Exchange 2010 SP2 UR4.  We are using Vault to archive mail from mailboxes.  (duh).

Due to some patching issues with Vault, we are trying to find out if there's a way to automatically export all email from all Vault mailboxes back into the existing Exchange mailboxes.  There are of course ways to use the GUI to do this for one mailbox/user, but is there a way, via the GUI or command line or using a CSV spreadsheet to do this unattended?

We have near 10K mailboxes, so, we're looking for a nice method/tool to do this.

Thank you in advance for any of your ideas and help.

Sincerely,

Michael Reinders