We are here from Techjoomla Team. We have some commercial products like Invitex and Broadcast which integrates with Facebook,linkedin and other social networks.
Actually if user logged in with JFBConnect some basic joomla login triggers of joomla are not working. Few of our clients are facing issues with Invitex.
We need to test our Invitex with JFbConnect. Can you please provide us subscription for JFBConnect.
We will also provide you Invitex and Broadcast subscription for you.
Sagar Techjoomla Team
I just created a subscription for you and you should be able to download JFBConnect from the My Account -> My Downloads area in the top right.
As for the authentication process, we use the standard JFactory::getApplication()->login('username', 'password') call to let Joomla handle the authentication. Our authentication plugin validates the user against a social network, and then Joomla calls the standard onUserLogin, onUserLogout, etc calls. We don't call them directly because we shouldn't need to. The login authentication code is in the /controllers/login.php file, though that calls plenty of other code based on the social network provider, if the user is new, etc.
Please feel free to get in touch here, or through our Contact Us form if you have any other questions. I did receive your Contact Us submission with the same post as above. It's simply easier to respond here, but we can easily talk through email or Skype if you'd prefer.
We'd love to hear about any issues you run into.
Ah nice to see you guys work together on compatibility. Hopefully we can see some collaborations on taking "Invite friends from Facebook" on Joomla to the next level. (P.S. I subscribe to both products, but currently only use JFBConnect, as I feel Invitex needs more work and a better interface.)