diff --git a/ggsn/Makefile.am b/ggsn/Makefile.am
index 3ad3a6e..c945f0b 100644
--- a/ggsn/Makefile.am
+++ b/ggsn/Makefile.am
@@ -12,7 +12,7 @@
 endif
 
 ggsn_DEPENDENCIES = ../gtp/libgtp.la ../lib/libmisc.a
-ggsn_SOURCES = ggsn.c cmdline.c cmdline.h gtp-kernel.h
+ggsn_SOURCES = ggsn.c cmdline.c cmdline.h gtp-kernel.h icmpv6.c icmpv6.h checksum.c checksum.h
 
 if ENABLE_GTP_KERNEL
 ggsn_SOURCES += gtp-kernel.c