After some debugging with Firebug – I tracked down that the problem was in the additional php file that the javascript calls in the Ajax functions: kk-ratings-ajax.php. This file is served (at least in my server) in ISO 8859-1 charset – instead of UTF-8. This probably happens because of the way it is called from a js file instead of normal browser request. If UTF-8 isn’t forced in the server-side, the file is (at least in Firefox or some of it’s versions) handled as ISO 8859-1. If ISO is embedded in UTF-8, it causes the output of the ISO-formatted file to start with few extra characters that seemed to mess up the javascript handling – causing the problems mentions above:
???SUCCESS|||54|||2.7/5(54%) 24 votes|||no
instead of the error free version:
SUCCESS|||54|||2.7/5(54%) 24 votes|||no
UTF-8 force-fed can be enabled from the .htaccess in the root of the www-site, by adding this line:
AddDefaultCharset UTF-8
That’s a way to go around it, but I’d love to see a proper fix into the issue. BTW this also fixes WP Stats plugin’s dashboard box which has the same characters appearing inside the box!