doc in makefile.am
diff --git a/Makefile.am b/Makefile.am
index 2f6d1c1..fcca031 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,2 +1,2 @@
 ## Process this file with automake to produce Makefile.in
-SUBDIRS = gtp ggsn sgsnemu
+SUBDIRS = gtp ggsn sgsnemu doc