title: Why php-mongodb extension fail to work?
body: <p>I find mongo.so mysql.so In my default extension dir /usr/lib/php5/20090626+lfs<br>
  Before they are all working well.<br>
  But today I have some update in my ubuntu,then mongo-extension fail to work in PHP.<br>
  But mongo.so is exist in the dir,and i add "extension=mongo.so" in /etc/php5/apache2/php.ini</p>