diff --git a/mongodb_block/mongodb_block.module b/mongodb_block/mongodb_block.module
index e0945f7..ce901aa 100644
--- a/mongodb_block/mongodb_block.module
+++ b/mongodb_block/mongodb_block.module
@@ -69,7 +69,7 @@ function mongodb_block_page_build(&$page) {
   $all_regions = system_region_list($theme);
 
   $collection = mongodb_collection('block', $theme);
-  if (!$collection->findOne()) {
+  if (!$collection->find(array(), array('_id' => TRUE))->limit(1)->hasNext()) {
     _mongodb_block_rehash($theme);
   }
   $query = array();