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--- a/Makefile.am
+++ b/Makefile.am
@@ -56,7 +56,7 @@
     libupnpp/base64.hxx \
     libupnpp/base64.cxx \
     libupnpp/expatmm.hxx \
-    libupnpp/getsyshwaddr.cxx \
+    libupnpp/getsyshwaddr.c \
     libupnpp/getsyshwaddr.h \
     libupnpp/ixmlwrap.cxx \
     libupnpp/ixmlwrap.hxx \