Pm on Report

On any report, will send a PM to moderators or admins, and can also deactivate email sending on setting. (post, album, image, visitor message)

Here is how you set it:

This setting is located in the Infractions Options, here:

AdminCP >> vBulletin Options >> User Infractions & Post Reporting Options

And here is the PM you receive when a post is reported:

As this is just a phrase, you can customize the text.