[fw-general] Limiting one user in zend_auth.

[Mr. Eric Eugene Naujock]

Is there a way to track sessions to prevent a user for creating an  
account a logging multiple times at once. I am not seeing anything  
that allows me to hook in and have the sessions check to see that  
account johndoe is not logged in more then once at one time. How would  
I go about doing this with zend _auth?