Vbulletin and Wishlist Registration combined as one registration

Hi, I hope you could help me, we have a very well established forum on the root directory of a domain like [[login to view URL]][1] We also want to run a membership site on Wordpress running Wishlist Member plugin on Wordpress in a folder called MEMBERS like [[login to view URL]][2] Now what we need to do is when someone hits our root domain and signs up with our vBulletin forum we would also like the registration details to pass into wishlist database so they get automatically signed up for a membership level in Wishlist. We just want to do away with them having to fill out two registration forms and only have one registration.