diff --git a/net/kamailio-5.x/Makefile b/net/kamailio-5.x/Makefile
index a8d099d..b9531b1 100644
--- a/net/kamailio-5.x/Makefile
+++ b/net/kamailio-5.x/Makefile
@@ -121,7 +121,7 @@ PKG_MAKE_ARGS:= \
 	cfg_target:=/etc/kamailio/ \
 	TLS_HOOKS=1 \
 	extra_defs="-DUSE_PTHREAD_MUTEX " \
-	CFLAGS="$(TARGET_CFLAGS)" \
+	CFLAGS="$(TARGET_CFLAGS) $(TARGET_CPPFLAGS)" \
 	LOCALBASE="$(STAGING_DIR)/usr" \
 	SYSBASE="$(STAGING_DIR)/usr" \
 	PCREDEFS:="$(TARGET_CPPFLAGS)" \