We have suffered a hacker attack and are working to recover from it.
Some nice and friendly soul has compromised our server and messed up our web applications and database server. Peace be with his simple mind.
His (or her) cleverness has, however, caused a lot of downtime since Saturday, and lots of work to isolate the issue.
We have not solved it, but the forums are now open. If you find that you get blank pages or other strange behaviour, try to hit the back button in your browser and try something else.
Some forums refuse to open, while others work fine. It is not clear why this happens.
You might also get logged out all of a sudden.
I am sorry for this situation but until we get this fixed things will be unstable.