1) Installed drupal-7.12 version on an nginx server , php-fpm version 5.4.0 got the following warning and notice
Warning: Illegal string offset 'field' in DatabaseCondition->__clone() (line 1901 of /webserver/nginx/html/drupal-7.12/includes/database/query.inc).
Notice: Array to string conversion in menu_link_save() (line 3112 of /webserver/nginx/html/drupal-7.11/includes/menu.inc).
Screen Shot is attached
When i changed the php version to 5.3 it is working fine .