Does this still work for folks? I'm hasing an issue with the login into the additional domains that I'm trying to track down.
Warning: in_array() [function.in-array]: Wrong datatype for second argument in /home/dariabe/public_html/wp-includes/wpmu-functions.php on line 218
Warning: in_array() [function.in-array]: Wrong datatype for second argument in /home/dariabe/public_html/wp-includes/wpmu-functions.php on line 218
Followed by the normal "Cant modify headers..." errors.
I have to see where 218 is within my wpmu-functions.php file as, for me, that's probably the most modified file I have.
edit: #218 is the check for site admins:
if( in_array( $user_login, $site_admins ) )