admin not working

i started a thread about theme editor not working: but i can’t find it and now it seems my whole admin interface does not work, whatever i click.

an example of the strings i get:

Warning: Cannot modify header information – headers already sent by (output started at /home/makisquare/www/www/wordpress/wp-content/themes/maki/functions.php:1) in /home/makisquare/www/www/wordpress/wp-includes/pluggable.php on line 275

???