Re: Special characters lost after upgrade
If it didn't work for you, then I have no more clues (it did work for me and other people yers ago when we had encoding issues).
Maybe just check with phpmyadmin or similar that you don't have any table or db encoding still in non-utf-8 encodind. If so, you should be able to change the encoding of the remaining table or db directly in phpmyadmin.
If this is not enough, then I would suggest that you look for hiring some consultant highly skilled in mysql encoding (not me, sorry; I just knew the recipies that worked for most of us).