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--- a/Makefile.am
+++ b/Makefile.am
@@ -9,6 +9,8 @@
 #    libupnpp/control/service.cxx 
 
 libupnpp_la_SOURCES = \
+    libupnpp/control/avlastchg.cxx \
+    libupnpp/control/avlastchg.hxx \
     libupnpp/control/cdircontent.cxx \
     libupnpp/control/cdircontent.hxx \
     libupnpp/control/cdirectory.cxx \