"ç" not rendering in date

My problem is that the character “ç” doesn’t render correctly in the date (for March in catalan: Març). It doesn’t have anything to do with the font, because I can see it in titles, content, excerpts, etc.

I have this in my header.php.

<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">

and I’m using a theme created by myself. Any idea what it might be?