setCookiePath only working on some of the cookies

Support & Bugs
1

Here is part of my code

window.piwikAsyncInit = function () {
try{
var tracker = Piwik.getAsyncTracker();
tracker.setCustomRequestProcessing(function (request) {
…
return request;
});
tracker.enableLinkTracking(true);
tracker.setTrackerUrl(url);
tracker.setSiteId(id);
…
tracker.setCookiePath(’/my/path’);

All of the cookie set by piwik is prefixed with _pk_id, and some of them have the path “/my/path”, but most of them have the default path “/”.

How do I set the cookie to all of them?