diff --git includes/entity.inc includes/entity.inc
index a212ff0..44acd25 100644
--- includes/entity.inc
+++ includes/entity.inc
@@ -767,7 +767,8 @@ class EntityFieldQuery {
     drupal_alter('entity_query', $this);
 
     // Execute the query using the correct callback.
-    $result = call_user_func($this->queryCallback(), $this);
+    $function = $this->queryCallback();
+    $result = call_user_func($function, $this);
 
     // Sanity checks.
     if (!empty($this->propertyConditions)) {