diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 5d55534..f828b52 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -69,6 +69,7 @@
 LOCAL_DROIDDOC_CUSTOM_ASSET_DIR:=
 LOCAL_DROIDDOC_OPTIONS:=
 LOCAL_DROIDDOC_HTML_DIR:=
+LOCAL_ADDITIONAL_HTML_DIR:=
 LOCAL_ASSET_FILES:=
 LOCAL_ASSET_DIR:=
 LOCAL_RESOURCE_DIR:=