Only in mailing_list_fix: mailing_list_fix_schema.patch
diff -urp mailing_list/mailing_list.install mailing_list_fix/mailing_list.install
--- mailing_list/mailing_list.install	2008-09-02 11:30:49.000000000 -0400
+++ mailing_list_fix/mailing_list.install	2008-11-10 19:37:23.671828220 -0500
@@ -33,10 +33,15 @@ function mailing_list_schema() {
     'description' => t('Emails subscribed to specific fields'),
     'fields' => array(
       'id'        => array(
-        'type'    => 'int',
+        'type'    => 'serial',
         'unsigned' => TRUE,
         'not null' => TRUE,
       ),
+      'mailing_list_id' => array(
+      	'description' => t('Which mailing list the address is subscribed to.'),
+      	'type' => 'int',
+      	'not null' => TRUE,
+      ),
       'email'  =>  array(
         'description' => t('The title of this mailing list'),
         'type' => 'varchar',
@@ -45,9 +50,6 @@ function mailing_list_schema() {
       ),
     ),
     'primary key' => array('id'),  
-    'unique keys' => array(
-      'sub'     => array('id', 'email'),
-      ),
   );
   
   
diff -urp mailing_list/mailing_list.module mailing_list_fix/mailing_list.module
--- mailing_list/mailing_list.module	2008-07-20 02:11:35.000000000 -0400
+++ mailing_list_fix/mailing_list.module	2008-11-10 19:13:56.944033195 -0500
@@ -81,7 +81,7 @@ function mailing_list_subscription_form_
     drupal_set_message('Error occured while saving your subscription. Please contact sie administrators', 'error');
     return ;
   }
-  $query = "INSERT INTO {mailing_list_emails} (id, email) VALUES (%d, '%s')";
+  $query = "INSERT INTO {mailing_list_emails} (mailing_list_id, email) VALUES (%d, '%s')";
   if (db_query($query, $form_state['values']['id'], $form_state['values']['email'])) {
     drupal_set_message('Your Subscription to <em>'. $form_state['values']['list'] .'</em> has been saved');
   }
@@ -167,4 +167,4 @@ function mailing_list_form_submit($form,
       drupal_set_message('Failed to Create New Mailing List: '. check_plain($form_state['values']['list_name']), 'error'); 
     }
   }
-}
\ No newline at end of file
+}