Joomla! Discussion Forums

So I've tried looking for this, but cannot find it anywhere.

Where/how can I change the default minimum password length?  I am creating a site that requires stronger (or weaker, depending what you are doing) passwords, and I want to be able to change them.

Test this extension: http://extensions.joomla.org/component/option,com_mtree/task,viewlink/link_id,2410/Itemid,35/