diff --git a/src/expat/lib/expat_external.h b/src/expat/lib/expat_external.h
index aa08a2f84c..6846e6bbc7 100644
--- a/src/expat/lib/expat_external.h
+++ b/src/expat/lib/expat_external.h
@@ -5,6 +5,13 @@
 #ifndef Expat_External_INCLUDED
 #define Expat_External_INCLUDED 1
 
+/* wxWidgets modification: always predefine XML_STATIC as we always use
+   Expat as a static library.
+*/
+#ifndef XML_STATIC
+#define XML_STATIC
+#endif
+
 /* External API definitions */
 
 #if defined(_MSC_EXTENSIONS) && !defined(__BEOS__) && !defined(__CYGWIN__)