I'm building a joomla 3 site and I'm using the corresponding version of datafeeds component. I noticed that, depending on the feed entries, some urls end up having some uppercase letters. If I manually go to the same url but with all the letters as lowercase then the same page is loaded again (instead of redirecting to the url with the uppercase letters or throwing a 404 error as it should), which ofcourse will be seen as duplicate content by the search engines.
Yes, I've already customized the router to make all urls lowercase, using mb_strtolower function, however if I manually enter the same url with any letter as uppercase then the same page is loaded, so the problem is there, and any competitor can black hat my ass by linking to multiple versions of the same page, changing only one letter at a time.
If I use sh404, it correctly 301 redirects to lowercase urls but it doesn't retain menu structure.
Maybe the solution is in .htaccess and httpd.conf to redirect to lowercase urls.
I'm also thinking of adding a rel=canonical to any url that has at least one uppercase letter in it (I prefer redirects though)