diff --git a/docs/Doxyfile.in b/docs/Doxyfile.in
index 4ec113e5..3a192d66 100644
--- a/docs/Doxyfile.in
+++ b/docs/Doxyfile.in
@@ -1783,13 +1783,13 @@ XML_OUTPUT             = xml
 # validating XML parser to check the syntax of the XML files.
 # This tag requires that the tag GENERATE_XML is set to YES.
 
-XML_SCHEMA             =
+#XML_SCHEMA             =
 
 # The XML_DTD tag can be used to specify a XML DTD, which can be used by a
 # validating XML parser to check the syntax of the XML files.
 # This tag requires that the tag GENERATE_XML is set to YES.
 
-XML_DTD                =
+#XML_DTD                =
 
 # If the XML_PROGRAMLISTING tag is set to YES doxygen will dump the program
 # listings (including syntax highlighting and cross-referencing information) to