cakePHP baseDir and baseUrl

Hi guys!

I'm trying to use CKFinder in combination with cakePHP.
This is my cakePHP webroot:
/app/webroot/
This is were CKFinder is located:
/app/webroot/js/ckfinder/

Now I got some problems with baseDir and baseUrl.
These are there current values:
$baseUrl = '/js/ckfinder/userfiles/';
$baseDir = resolveUrl($baseUrl);
But when I'm now trying to upload an image, I get this error:

It was not possible to complete the request due to file system permission restrictions.

Hope someone can help me!

Thanks!