WordPress OpenID (server?)

I was thinking, since wp-united is far from finished, to set up my wordpress with OpenID and using that to bridge it to my PHPBB3 site which will also use OpenID login then. First of all, is this bridge possible?

Now I also ask myself, do I have to install an OpenID server on my server?

Users will have to remain on my site, and not be redirected to create an openID.

How would I best start this?

Note: I just installed OpendID plugin – which says it also acts as An OpenID server , thus provider.