diff --git a/siu/l2tp/Makefile b/siu/l2tp/Makefile
index ba7bde5..86734c2 100644
--- a/siu/l2tp/Makefile
+++ b/siu/l2tp/Makefile
@@ -8,7 +8,7 @@ CFLAGS += $(EXTRA_CFLAGS)
 
 all: l2tpd
 
-l2tpd: l2tpd.o l2tpd_fsm.o l2tpd_data.o l2tpd_packet.o l2tpd_socket.c l2tpd_lapd.c
+l2tpd: l2tpd.o l2tpd_fsm.o l2tpd_data.o l2tpd_packet.o l2tpd_socket.c l2tpd_lapd.c crc32.c
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
 %.o: %.c