diff --git a/configure.ac b/configure.ac
index ac0e31d..12ad8f7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,7 +3,7 @@
 
 AC_PREREQ([2.65])
 AC_INIT([mosh], [0.96a], [mosh-devel@mit.edu])
-AM_INIT_AUTOMAKE([-Wall -Werror])
+AM_INIT_AUTOMAKE([-Wall -Werror foreign])
 AC_CONFIG_SRCDIR([src/frontend/mosh-client.cc])
 AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_HEADERS([config.h])