I have a problem creating an input validation hash. JavaScript submits data to API and API validates the sent data with json_encode. Basically it works like this:

$input=array('name'='John Doe','city'=>'New York');

$validationHash=sha1(json_encode($input).$key); // Key is known to both servers

If PHP connects to another server, then everything works. It also works through JavaScript (I have a custom sha1() function there as well):

var validationHash=sha1(JSON.stringify({'name':'John Doe','city'=>'New York'})+key);

My problem comes when the string contains UTF-8 characters. For example, if one of the values is:

Ränisipelgasöösel

Then PHP server that receives the command converts it to this after JSON encoding:

Ru00e4nisipelgasu00f6u00f6sel

I need to do this in JavaScript as well, but I haven't been able to work out how. I need to make sure that I send proper validation hash to the server or the command fails. I found from Google that unescape(encodeURIComponent(string)) and decodeURIComponent() could be used, but neither gives me the same string that PHP has and validates with.

UTF-8 is used on both client and server.

Any ideas?