diff --git a/boxes.module b/boxes.module
index 8de7978..3f0f7a1 100644
--- boxes.module
+++ boxes.module
@@ -100,7 +100,7 @@ function boxes_block_info() {
     // Let context group the instances together
     $blocks[$box->delta]['context_group'] = t('Boxes for @plugin', array('@plugin' => $plugins[$box->plugin_key]['title']));
     // Let each box determine how it is cached
-    $blocks[$box->delta]['cache'] = $box->cache_setting();
+    $blocks[$box->delta]['cache'] = method_exists($box, "cache_setting") ?  $box->cache_setting() : DRUPAL_CACHE_CUSTOM;
   }
 
   // 'Add' blocks for editing a page inline