diff --git a/include/openbsc/Makefile.am b/include/openbsc/Makefile.am
index 109f3c8..062df34 100644
--- a/include/openbsc/Makefile.am
+++ b/include/openbsc/Makefile.am
@@ -1,4 +1,4 @@
 noinst_HEADERS = abis_nm.h abis_rsl.h debug.h db.h gsm_04_08.h gsm_data.h \
 		 gsm_subscriber.h linuxlist.h msgb.h select.h tlv.h gsm_04_11.h \
 		 timer.h misdn.h chan_alloc.h telnet_interface.h paging.h \
-		 subchan_demux.h trau_frame.h e1_input.h trau_mux.h
+		 subchan_demux.h trau_frame.h e1_input.h trau_mux.h signal.h