diff --git a/src/modules/xforms/xforms.py b/src/modules/xforms/xforms.py
index cb0f419..68e17d6 100644
--- a/src/modules/xforms/xforms.py
+++ b/src/modules/xforms/xforms.py
@@ -487,6 +487,7 @@ class Control(WidgetElement):
             return False
         return bind.isRequired(
             context, modelContext, self.getInstanceDataXpath(context, modelContext))
+        # FIXME: should also look in the schema: "xsd:element[not(@minOccurs) or @minOccurs > 0] | xsd:attribute[@use='required']"
 
     def setFieldValue(self, context, modelContext, fieldValue):
         valueNode = self.getInstanceDataNode(context, modelContext)