--- a/sites/all/modules/comment_notify/comment_notify.install
+++ b/sites/all/modules/comment_notify/comment_notify.install
@@ -62,7 +62,8 @@ function comment_notify_schema() {
         'description' => 'A boolean indicator for whether or not a notification for the comment has been sent: 1 means yes, 0 means no.',
         'size' => 'tiny',
         'not null' => TRUE,
-        'disp-width' => '11'),
+        'disp-width' => '11',
+        'default' => 0),
     ),
     'primary key' => array('cid'),
     'indexes' => array(