constant_contact.patch

diff --git a/constant_contact.module b/constant_contact.module
index d490544..a2f0ae0 100755
--- a/constant_contact.module
+++ b/constant_contact.module
@@ -1099,7 +1099,6 @@ function constant_contact_signup_form($form, &$form_state, $delta)
 	return $form;
 }
 
-
 /**
  * Custom signup form submit handler
  */
@@ -1178,25 +1177,30 @@ function constant_contact_signup_form_submit($form, &$form_state)
 	$lists = array_keys($lists);
 
 	if($contact):
-		form_set_error('cc_email_'.$delta, t('Your email address is already subscribed'));
+    // SV: Old logic was to fail with error message if contact already exists.
+    // New logic is to continue without error and merge selected lists with
+    // those already assigned to contact. (Unselected lists are not removed
+    // from contact as this form is unprotected.)
+    $loaded_contact = $cc->get_contact($contact[id]);
+    $existing_lists = $loaded_contact['lists'];
+    $lists = array_unique(array_merge($lists, $existing_lists));
+    $status = $cc->update_contact($contact['id'], $user_email, $lists);
 	else:
 		$status = $cc->create_contact($user_email, $lists, $fields);
+  endif;
 
-		if($status):
-			if(!$redirect_to):
-				drupal_set_message(t('Success, you are now subscribed to our mailing list'));
-			endif;
-		else:
-			form_set_error('cc_email_'.$delta, t('Sorry, there was a problem, please ensure your details are valid and try again'));
+  if($status):
+		if(!$redirect_to):
+			drupal_set_message(t('Success, you are now subscribed to our mailing list'));
 		endif;
-
+	else:
+		form_set_error('cc_email_'.$delta, t('Sorry, there was a problem, please ensure your details are valid and try again'));
 	endif;
 
 	$form_state['redirect'] = $redirect_to;
 	return;
 }
 
-
 /**
  * Cron job to handle syncing unsubscribers
  */