spivurno

/**
* Configure Admin Approval for New Accounts
* http://gravitywiz.com/
*/
remove_filter('wpmu_signup_user_notification_email', array('GFUserSignups', 'modify_signup_user_notification_message'));
add_filter('wpmu_signup_user_notification_email', 'my_modify_signup_user_notification_message');

function my_modify_signup_user_notification_message() {        
    return false;
}