Here is the fixed function for Turkish alphabet..
<?php
function uc_first($str){
$str[0] = strtr($str,
"abcdefgh?ijklmnopqrstuvwxyz".
"\x9C\x9A\xE0\xE1\xE2\xE3".
"\xE4\xE5\xE6\xE7\xE8\xE9".
"\xEA\xEB\xEC\xED\xEE\xEF".
"\xF0\xF1\xF2\xF3\xF4\xF5".
"\xF6\xF8\xF9\xFA\xFB\xFC".
"\xFE\xFF",
"ABCDEFGHI?JKLMNOPQRSTUVWXYZ".
"\x8C\x8A\xC0\xC1\xC2\xC3\xC4".
"\xC5\xC6\xC7\xC8\xC9\xCA\xCB".
"\xCC\xCD\xCE\xCF\xD0\xD1\xD2".
"\xD3\xD4\xD5\xD6\xD8\xD9\xDA".
"\xDB\xDC\xDE\x9F");
return $str;
}
?>