diff --git a/reference/mongo/mongogridfs/storefile.xml b/reference/mongo/mongogridfs/storefile.xml
index 2a0d38c34a..3eb708dd3a 100644
--- a/reference/mongo/mongogridfs/storefile.xml
+++ b/reference/mongo/mongogridfs/storefile.xml
@@ -10,7 +10,7 @@
  <refsect1 role="description">
   &reftitle.description;
   <methodsynopsis>
-   <modifier>public</modifier> <type>mixed</type><methodname>MongoGridFS::storeFile</methodname>
+   <modifier>public</modifier> <type>MongoId</type><methodname>MongoGridFS::storeFile</methodname>
    <methodparam><type>string</type><parameter>filename</parameter></methodparam>
    <methodparam choice="opt"><type>array</type><parameter>extra</parameter><initializer>array()</initializer></methodparam>
    <methodparam choice="opt"><type>array</type><parameter>options</parameter><initializer>array()</initializer></methodparam>