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--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,7 @@
 AC_INIT([upmpdcli], [1.2.16], [jfd@lesbonscomptes.com],
              [upmpdcli], [http://www.lesbonscomptes.com/upmpdcli])
 AC_PREREQ([2.53])
+AC_CONFIG_MACRO_DIRS([m4])
 AC_CONFIG_SRCDIR([src/upmpd.cxx])
 AC_CONFIG_HEADERS([src/config.h])
 AH_BOTTOM([#include "src/conf_post.h"])
@@ -72,6 +73,9 @@
 
 LIBS=""
 
+#### Functions
+AC_FUNC_LIBUPNPP_LINNSONGCAST
+
 AC_SUBST(UPMPDCLI_LIBS)
 AC_SUBST(SCCTL_LIBS)