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--- a/configure.ac
+++ b/configure.ac
@@ -26,6 +26,7 @@
 AC_PREREQ([2.53])
 AC_CONFIG_SRCDIR([libupnpp/upnpplib.hxx])
 AC_CONFIG_HEADERS([libupnpp/config.h])
+AH_BOTTOM([#include "libupnpp/conf_post.h"])
 
 AM_INIT_AUTOMAKE([1.10 no-define subdir-objects foreign])
 AC_DISABLE_STATIC