php encoding issue htmlentities

Question

I have user input and use htmlentities() to convert all entities. However, there seems to be some bug. When I type in

ääää öööö üüüü ääää

I

Answer 1

it is important that 3th parameter of htmlentities matches the character set that uses the post. I supouse, you are NOT submiting utf8, as it is the default in htmlentities

in PHP

 $post = htmlentities ( $post, ENT_COMPAT, 'ISO-8859-1')  // or whatever  

in Form

anyway, actualy I recommend you to use utf8