Add cookie for authentication of REST GET

Hi,

We want to authenticate for a REST GET call with a cookie. 

If we test this in the browser with an URL with a username and password this works (to add the Cookie) for a successful call.

If we try to use te RestServices.addCookieToNextRequest java action we get "Response status: 401 Unauthorized", when we try to make the call.

Is it possible to add authentication via an URL (with username and password) with this java action and how should the values (name, value, maxageseconds, path, domain, httponly) be configured? (Trying to rebuild the cookie that is visible in the browser does not work for us). Or can we do it another way?

Thanks a lot,

Martijn