Exchange 2010 is the first version of Exchange to implement the moderated transport feature. This allows you to require approval for all e-mail messages sent to a particular recipient by a designated moderator. In this recipe, you'll learn how to configure the moderation settings on recipients using the Exchange Management Shell.
Set-DistributionGroup -Identity Executives ` -ModerationEnabled $true ` -ModeratedBy administrator ` -SendModerationNotifications Internal
Set-Mailbox -Identity dave ` -ModerationEnabled ...