Phabricator requires login to view patches

Hi,

I just tried to view a diff at:

http://reviews.llvm.org/differential/diff/9189/

and I am only shown a "Login" prompt. Did I do something wrong or am I by design asked to login to _view_ a diff. If this is by design, would it be possible to make diffs accessible without login?

Cheers,
Tobias

Filed upstream:
https://secure.phabricator.com/T5303