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--- a/Makefile.am
+++ b/Makefile.am
@@ -41,6 +41,8 @@
     libupnpp/ptmutex.hxx \
     libupnpp/soaphelp.cxx \
     libupnpp/soaphelp.hxx \
+    libupnpp/upnpavutils.hxx \
+    libupnpp/upnpavutils.cxx \
     libupnpp/upnpp_p.hxx \
     libupnpp/upnpplib.cxx \
     libupnpp/upnpplib.hxx \