So, some examples:
1. I register at a normal vBulletin Forum with this Add-on:
Attachment 87118
Now I get a verify email for my vBulletin Account. After I'm verify my vBulletin Account, the Forum send my Registration Data to the Openfire Server (without the vBulletin Password).
I get a seperat email with my Openfire Account details with a seperat Password:
Attachment 87119
Now I'm registered at my Forum and my Openfire Server.
Example with meebo:
I going to meebo.com and click more networks. Under Jabber I give my Openfire Account details:
Attachment 87120
So Im Log In to Meebo and add a Google Talk User:
Attachment 87121
I have make a dirty @ on the Screenshots because I dont like spambots.
More examples cooming soon.