The URL structure for foreign characters (Spanish, Portuguese etc.) is poor if you choose the first option for URL structures, which is really the only option for SEO purposes.
What happens is that the URL structure keeps foreign characters, like ç or ã in the URL instead of replacing these with a regular c or a. This will cause problems because the canonocial URL will have % URL encoding characters instead of regular letters. Not good for SEO or usability.
This is relatively simple to fix with a preg_replace. But, where in the code is the URL created so that one can simply replace all foreign characters with their regular counterpart?