Joomla supports out of the box the UTF-8 character encoding, so someone building a multilingual website should not have any problems using UTF-8 character encoding in his site. Right?
Yes and no, the CORE Joomla is problem free as I write this, but some non-core add-ons, templates - and yes, your own, home-cooked code can produce garbled output. Let's see why, and how we can fix it!