diff --git a/include/osmocom/Makefile.am b/include/osmocom/Makefile.am
index 4d80637..b07a004 100644
--- a/include/osmocom/Makefile.am
+++ b/include/osmocom/Makefile.am
@@ -1,3 +1,4 @@
 SUBDIRS = \
 	msc \
+	smpp \
 	$(NULL)