Require Referral to Register?

[isman]

Hi,

I have a forum running that requires registration by invitation only. I need the registration process to require that they have to enter the name of the member who referred them to the site when registering. And I need it to verify that the information is correct (that there actually is a member with that name).

I'd prefer to utilize the referral system if possible but don't know what to modify to get this working right.

Any help is appreciated.

Lana