publishing content

I'm looking for information on how to setup Rules to automatically update the "created on" date of a node to the current date and time when that node is changed from "unpublished" to "published".

Basically, the site accepts content from registered users, which is not published until an admin/moderator reviews it. Upon review, the node's status is changed from "unpublished" to "published". At that moment, I'm trying to configure Rules to update the node's creation date to the current date and time (so that its creation date is the time it was published, not actually created).