I did a lot of PHP programming in the last years and one thing that keeps annoying me is the weak support for Unicode and multibyte strings (to be sure, natively there is none). For example, "htmlentities" seems to be a much used funtion in the PHP world and I found it to be absolutely annoying when you've put an effort into keeping every string localizable, only store UTF-8 in your database, only deliver UTF-8 webpages etc. Suddenly, somewhere between your database and the browser there's this hopelessly naive function pretending every byte is a character and messes everything up.
I would just love to just dump this kind of functions, they seem totally superfluous. Is it still necessary these days to write 'ä' instead of 'ä'? At least my Firefox seems perfectly happy to display even the strangest Asian glyphs as long as they're served in a proper encoding.
Update: To be more precise: Are named entities necessary for anything else than displaying HTML tags (as in "<" for "<")
Update 2:
@Konrad: Are you saying that, no, named entities are not needed?
@Ross: But wouldn't it be better to sanitize user input when it's entered, to keep my output logic free from such issues? (assuming of course, that reliable sanitizing on input is possible - but then, if it isn't, can it be on output?)