Description:
------------
the latest version of mongodb driver (1.2.3) does not support insert.

.........
$collection->insert(array('user' => $username, 'pwd' => md5($username . ":mongo:" . $password) , 'readOnly' => $readOnly), array('safe' => true));
.........

I got this output:

..Segmentation fault

After I reinstalled mongodb driver (1.1.4), the problem was solved.

Test script:
---------------
.........
$collection = $this->mongo->selectDB($databaseName)->selectCollection("system.users");

$collection->insert(array('user' => $username, 'pwd' => md5($username . ":mongo:" . $password) , 'readOnly' => $readOnly), array('safe' => true));
.........

Expected result:
----------------
can run 

Actual result:
--------------
..Segmentation fault