Ok, I done this; here is what worked for me:
1. add this code to
wp-config:
if(is_admin()) {
add_filter('filesystem_method', create_function('$a', 'return "direct";' ));
define( 'FS_CHMOD_DIR', 0751 );
}
2. change permission to 777 on upgrade folder
3. change permission to 777 on Akismet folder (777 on plugins folder wasnt enough..)