External Authentication hack?

[iflc_sw_procure]

I am interested in purchasing vBulletin, but before my organization can do so, we need to ensure we can integrate it with our existing system.

Specifically, what we need to be able to do is have user authentication done through an external system. This will prevent users from having to have a separate username and password for our existing integrated systems and vBulletin.

We can modify the php code, but without being able to see how it works before purchasing, we have no way of knowing how difficult the task would be.

Ideally, if someone logs into their customized homepage at our site, then clicks on a "Forums" link, they should automatically be logged into vBulletin. If they try to access vBulletin and are not logged in, they should be directed to a standard login page (and from there they would be sent back to vBulletin after logging in).

If a logged in user tries to access vBulletin and has never done so before, it should prompt them for their initial user settings or just give them some initial default values (and perhaps display some kind of message like "Welcome to the forums. To configure your forums account, use the configuration link at the top of the page".

Again, what we want to avoid is users having to create multiple user accounts to use any of the systems on our web site.

Any assistance/info would be greatly appreciated.