I'm not so sure this should be in the main ULib/ULX help section.
We didn't write Sourcebans, nor have we written any module for it.
If you perform "ulx ban" from game or server console, does the person get banned from the server (ignoring sourcebans for now)?
If the person does, ULX is doing it's job, and this thread should be moved to a) off-topic b) somewhere into the discussion somewhere around here that actually discusses ulx integration c) developers corner.