Android : Create package directory in ../Android/data denied on SD-Cards on Android >4.4

I have trouble creating the "com.foo.Example" folder of my app in "/storage/extSdCard/Android/data" from inside the app. If created manually with a file manager there is no trouble, just creating the first one with a simple mkdir returns false. So once the "/storage/extSdCard/Android/data/com.foo.Example" is created I can write and remove files and folders to and from it. I used the package name declared in the manifest and used throughout and I do have the appropriate WRITE_EXTERNAL_STORAGE-permission in there aswell. Where is this folder suposed to come from, if the app is unable to create it?