Remove login confirmation message programmatically
You can add a custom module hook to alter the login process and unset the messages. If you look at core's user.module you can see the various points where you can hook into the login functions. 

This is one option (I think there are several and you may need to adjust based on your site's settings) You should be able to do something along these lines:

function YOURMODULE_user_login(&amp;$edit, $account) {
  if ($account-&gt;uid) {
     if (isset($_SESSION['messages']['status'])) {
       unset($_SESSION['messages']['status']);
     }
  }
}