diff --git a/includes/common.inc b/includes/common.inc
index bbf857bb96f..afa3cb3bcbb 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -640,7 +640,7 @@ function format_size($size) {
 }
 
 function cache_get($key) {
-  $cache = db_fetch_object(db_query("SELECT data, created FROM cache WHERE cid = '%d'", $key));
+  $cache = db_fetch_object(db_query("SELECT data, created FROM cache WHERE cid = '%s'", $key));
   return $cache->data ? $cache : 0;
 }