diff --git a/modules/forum/forum.install b/modules/forum/forum.install
index 60c4087..4bbd199 100644
--- a/modules/forum/forum.install
+++ b/modules/forum/forum.install
@@ -234,6 +234,18 @@ function forum_schema() {
 }
 
 /**
+ * Implements hook_update_dependencies().
+ */
+function forum_update_dependencies() {
+  // Forum update 7003 uses field API update functions, so must run after
+  // Field API has been enabled.
+  $dependencies['forum'][7003] = array(
+    'system' => 7020,
+  );
+  return $dependencies;
+}
+
+/**
  * Add new index to forum table.
  */
 function forum_update_7000() {