Undefined gray box for non loggeg in users

#### Steps to reproduce the issue

access e.g. this page but don't login:
http://issues.joomla.org/tracker/jtracker/584

#### Expected result

If nothing is in the box we can remove it to have more space for the rest.

#### Actual result

![gray_box](https://cloud.githubusercontent.com/assets/2596554/5565452/b3973ea4-8efd-11e4-8a2d-f1ca22f75773.PNG)