Well, then it is not a bug in strlen, but then it is a bug in your approach.

If we use www.php.net/manual/fr/function.mb-strlen.php in PHP, need a mb_strlen in javascript …
Or maybe our JS have an issue

holch wrote: I did not use any special characters, if I recall right (just have a look at the last result in your demo and you'll see my text).

k, then let's call it a Limesurvey bug

We have added a note about the special characters so users won't be confused.

I wouldn't consider the apostrophe a special character. If it doesn't count those right, the whole approach is worthless in my opinion.

You can't tell your respondents: Here is a character count, but it might not count some characters right...