White Page (of Death?)

Heyo

Suddenly my wp-site just gone completely white. I´ve done nothing, I´ve changed nothing it just turned white and I can´t access the admin board.

I´ve been looking around the forums and tried stuff that is suggested – no joy.
I have two failures:

1/ http://www.ljungbymk.com/
White page.

2/ “Fatal error: Call to undefined function _wp_filter_build_unique_id() in /customers/ljungbymk.com/ljungbymk.com/httpd.www/wp-includes/plugin.php on line 68”

When trying to access the loginpage (http://www.ljungbymk.com/wp-login.php).
The thing about the second fail is that I don´t have a folder called what it sais – never has. So I don´t have a clue how it could be like that.

So any ideas? – since im completely dry!