Subscription Referral - get referred and boost your own expiry date

[UDPride]

Ive looked but cant find a hack for this.

Basically we sell subscription to a particular premium forum. Real simple. However to boost subscriptions Id like to be able to have a new subscriber enter the name of another member who referred them to order a subscription.

For instance, User A whos asubscription member suggests to user B, "hey this scribby is great! you need one! sign up and mention my name." So user B signs up, and in so doing, enters the referral persons board handle.

User B gets the standard subscription like everyone else when the PayPal comes back and has the normal expiry date term, but User A gets X number of days added to their current subscription term for getting a referral.

We sell 1, 2, and 3yrs memberships to the premium forum, so if someone gets referred on a 1yr scribby, say they get 30 days added to their own, someone signs up for 2yrs and enters their name, they get 45 days, 3yrs and 60 days.

This would seem like a REAL easy hack. Just add a place on the payment.php page to add a box to enter the handle of someone who referred you.

Set it up on CP as a referral mod where you can set the "reward" in x days for each subscription term you offer.

Any thoughts? Im kind of surprised this isnt standard in VB to be quite honest.