diff --git a/source/tools/atlas/AtlasScript/ScriptInterface.h b/source/tools/atlas/AtlasScript/ScriptInterface.h
index c4cc3fc669..55a84422c2 100644
--- a/source/tools/atlas/AtlasScript/ScriptInterface.h
+++ b/source/tools/atlas/AtlasScript/ScriptInterface.h
@@ -32,6 +32,12 @@
 // (There are a few places where SM really needs to be told to be threadsafe, even
 // though we're not actually sharing runtimes between threads.)
 
+#if JS_VERSION <= 160
+// 1.6 doesn't support the standards-conforming globals behaviour,
+// so we can't use this flag there
+# define JSCLASS_GLOBAL_FLAGS 0
+#endif
+
 class wxWindow;
 class wxString;
 class wxPanel;