If you are in /notes/ and an URL links to /forums following that link will *not* take you to /notes/forums/ unless you're using a very broken browser (which would surprise me). If the link target starts with a slash it is locked to the root of the server URL tree.
Take a look at the source of the served HTML page where this link is - I'd be pretty confident that the link target is not actually coming through as "/forums"...
