XF 1.2 Moderating first post(s) of new users

I'd like to know if it's possible to set this up within Xenforo: A new user goes through the standard registration process and validates his email address, but after submitting his first post, it doesn't instantly show up on the site until it's validated by a moderator. This moderation process continues until the user reaches a certain number of posts (like 3 for example) and then that user is automatically promoted to a usergroup that doesn't have that moderation restriction.