When is fault-join-slot called?

Hi,

Quick question: is fault-join-slot also triggered in a setf form? For
example, will the following form also trigger fault-join-slot?

(setf (slot-value parent-obj join-slot) join-object)

I'm seeing weird behaviour in some of my code, which is expecting me
to believe that this is the case.

Also, where exactly is the MOP configured to hook into this function?

Nandz.
-- 
http://nandz.blogspot.com
http://foodieforlife.blogspot.com