When trying to access Security Domains under Profile/Security tree, the call blocks. Tested on CentOS 6 and Windows 7 machine, and behaviour seems to be the same. Did not see problems with other parts of web console. Also security domains seem to be working when configured from CLI.
Also once you click on "Security Domain" the whole console stops responding to the mouse, and web refresh is needed to get it back.
On the same (Linux) machine this works in Beta1.