'upgrade1_5.php', can do this -- run it prior to 'update.php' or
the web upgrader.
+NOTE that upgrade1_5.php does not work properly with recent version
+of MediaWiki. If upgrading a 1.4.x wiki, you should upgrade to 1.5
+first. upgrade1_5.php has been removed from MediaWiki 1.21.
+
If you absolutely cannot make the UTF-8 upgrade work, you can try
doing it by hand: dump your old database, convert the dump file
using iconv as described here: