is it now possible to make a SSO between vBulletin 3 und vBulletin 4?

Not yet, keep watching...

Do you need WordPress in order to use this plugin?
I just want a simple way to grab user data outside of Vbull?

Of course, in case if you want WordPress users to have a single sign-on. At this moment plugin is not designed to do export of the users at once. If moves only the users to WordPress on demand as soon as they are logged in to vBulletin. If you just need to move users it would make more sense to create a migration for your project and would be able to help wit this. We will consider the achievements of your goal if you drop us a PM message in more details.

Thank you,

Hi,

Sorry if the question has already been asked. I couldn't find it by searching.

What I wanted clarified is that if I installed this on two different vBulletin 4 forums that I owned and had installed on different domains people would only have to register on one and they could access the other too right?

Or am I mixing things up her.

But if this is how it works can it be used across vB4 forums that don't belong to me such as those that might want to collaborate with my forum?

Also where are the credentials stored?

Thanks for any help.

Right.

The new version of the product is almost ready to come out. It actually supports the connection of multiple forums to a single master's vBulletin.

The original credentials and stored in master's vBulletin instance. The vBulletin instance might be chosen on your own. All the connected platforms have no access to passwords, and the users located on the connected platforms are authenticated through master's vBulletin instance.

^^ Sounds exciting, I cannot wait to try out the new version.

Thanks for your detailed reply.

I also look forward to the new version. :)

Updates are just finally came out and could be grabbed from http://vbsso.com/download/ to inspire vBulletin 3.x compatibility and connection of multiple vBulletin forum instances.

Followed the posted instructions, tested platforms are VB 3.8 and WP 3.4 Multisite/Network. At first, the single sign on was working no problem. However, after logging in and posting comments with a couple test accounts it does not seem to work any more.
I visit the wordpress site and click log-in. VbSSO then redirects to Vb forum to log-in, and then redirects back to the wordpress site, however the user is never logged in and remains a guest. I also cannot log out of the super admin account. Any thoughts?

edit to add the error from my log-
Unrelated - I see that all Vbulletin users automatically get created as a Subscriber role in Wordpress, is there any way to customize this so that certain VB usergroups will be created as a different Wordpress user role? For example, a Vbulletin user who is a Moderator signs in using VbSSO, and instead of being stuck as a Subscriber, they are automatically made into an Editor role.