New wp 3.3 installation, impossible to modify widget

Hi,

i’ve just installed a clean wp 3.3 on a client’s server, but i get some strange behaviour in the admin area.

The sub-menu won’t appear after the mouse over, the post editor won’t show any formatting button (and any text in the post content appears in white), in the widget editor it’s impossible to drag-n-drop any widget to the bar o change anything.

i’ve tried to turn on the debug on wp-config

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);
@ini_set('display_errors',0);

but the debug.log is never updated with anything.

Permissions are set to 660 (file) and 770 (dir) and i can’t change them.

Any hint to solve the issue?

thank u