PM Limits by usergroup?

[TheEDIGuy]

I'm running 2.2.8, and we just recently had a group of users who decided to leave the site for another. The problem is, they keep coming back to our site to PM our other users to invite them to the new place. Our other users are starting to complain.

I know that 3.0 will have the ability to limit PM mailbox size by user group, but that's not completely what I'm looking for.

What I'd like to have is a limit to the number of PM's per (day, hour, whatever) that a user can send, which is configurable by user group. So, I could place these user accounts in a group that had a limit of, say, 2 PM's per day, while the regular user group would get more.

I'd also use this for new members, to restrict PM spammers.

Any takers? Thanks in advance!