diff --git a/configure.ac b/configure.ac
index 220124a..3dba3b3 100755
--- a/configure.ac
+++ b/configure.ac
@@ -442,7 +442,7 @@
 dnl -------------------------
 AC_CHECK_HEADERS([stropts.h sys/ksym.h sys/times.h sys/select.h \
 	sys/types.h linux/version.h netdb.h asm/types.h \
-	sys/param.h limits.h signal.h \
+	sys/cdefs.h sys/param.h limits.h signal.h \
 	sys/socket.h netinet/in.h time.h sys/time.h])
 
 dnl Utility macro to avoid retyping includes all the time