Integrating UBB Threads and Drupal

Our web site is being converted to Drupal but we need to keep UBB Threads. How do we integrate it into Drupal, keeping it password protected for our members *without* implementing a second log in process within UBB itself.

In other words. We want people who are members to seamlessly have access to UBB without having to log in a second time to the BBS.

1) How do we provision new UBB.threads accounts correctly since Drupal will be driving, not creating users via the UBB admin area?

2) What is the syntax for the magic cookie that Drupal should set when a Drupal login event happens successfully?

3) Is there a way to sync UserIDs and Passwords between Drupal and UBB? The front door will be mandatory Drupal and users will not be able to log into UBB. So could we possibly blank out the ability to log in via UBB?

4) Syntax for adjusting that cookie when a Drupal logout event occurs so UBB.threads no longer thinks the user is properly authenticated.