exported xmlXPathNodeSetAddNs()
diff --git a/win32/libxml2.def.src b/win32/libxml2.def.src
index 7831256..007444b 100644
--- a/win32/libxml2.def.src
+++ b/win32/libxml2.def.src
@@ -1444,6 +1444,7 @@
 	xmlXPathNewValueTree
 	xmlXPathNodeSetAdd
 	xmlXPathNodeSetAddUnique
+	xmlXPathNodeSetAddNs
 	xmlXPathNodeSetSort
 	xmlXPathIdFunction
 	xmlXPathRoot